THE UNIVERSITY OF MICHIGAN RESEARCH INSTITUTE ANN ARBOR, MICHIGAN Final Report MACHINABILITY EVALUATIONS OF TEN LOTS OF 2011-T3 ALLOY L. V. Colwell J. C tazur UMRI Project 2575 REYNOLDS METALS COMPANY RICHMOND, VIRGINIA July 1958

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ABSTRACT This study was a continuation of previous work performed in an automatic screw machine. Feeding-force transducers were added for all operations. These indicated that abnormal size variation was accompanied or caused by corresponding increases in feeding forces. Several prepared material variations plus two competitive alloys were studied in this manner. ii

INTRODUCTION The desirability of evaluating materials on the basis of extensive machinability tests, such as might be performed on an automatic screw machine, was demonstrated rather convincingly in Machinability Studies of Eight PreparedVariable Combinations of 2011-T3 Aluminum Alloy (Univ. of Micho Engo Res. Inst. Report 2575-1-P, Ann Arbor, June, 1957.) Several different sharp-tool tests were carried out in that program, but even though the tests did reveal some significant information, no evaluation of the variables could be made with any degree of consistency. The tests on the automatic screw machine, however, were very encouraging. Consistent trends were developed which divided, very sharply in many cases, the desirable from the undisirable variable combinations. An analysis of the above investigation revealed a need for further study of the 2011-T3 alloy. In addition, it was advisable to make a comparison in machinability of the same alloy produced by other suppliers. This report presents the results of that study. TEST MATERIALS A brief description of the various 2011-T3 alloy variable combinations is given in Table I along with the identifying symbols which are used throughout the report. The two materials, 122 and 221, which were not tested in the first series of tests, have been included in this study. TEST SETUP AND PROCEDURE Except for improved and more complete instrumentation, the entire test program was basically identical to the one used in the first series of investigations. Reference is made to Univ. of Mich. Eng. Res. Inst. Report 2575-1-P for details of machine setup and test procedure. Improved instrumentation permitted a much more complete study of tool feeding forces. Specially designed force dynamometers were mounted on the front and rear slides of the Brown and Sharpe screw machine to record the feeding forces on the light- and heavy-form tools. In addition, strain gages were mounted on the follower arm of the turret slide to measure, in particular, turning feeding force and drilling thrust. All forces were recorded on a 4-channel Sanborn recorder. Power and spindle-speed readings were recorded as before. 1

TABLE I TEST MATERIALS*. VARIATIONS OF 2011-T3 ALUMINUM ALLOY Identifying ^. ^. LLot Identifying Material Description Lot Symbol Number A Alcoa, standard stock G German, standard stock T1 High silicon E 807-A T2 Heat-treated, drawn (standard) E 808-A T3 Heat-treated, centerless ground, drawn E 809-A T4 Centerless ground, heat-treated, drawn E 810-A T5 Poor spray quench E 811-A T6 Good dip quench E 812-A 122 SLow copper, high heat-treat E 740 Temperature, high reduction 221 [High copper, high heat-treat E 758 (Temperature, low reduction All Reynolds materials except materials A and G. One operation, chasing, and one inspection step, tool inspection on the machine at intervals during a test, were eliminated. It was felt that the threading operation did not reveal enough significant information to distinguish between the materials, and that the difficulty of making accurate tool-wear measurements on the machine gave rise to inconsistent results which had little value With the above exceptions, no other changes were made in the test procedure. TEST RESULTS The test results on all materials are summarized in Table III. Tables IV and V show the tool-wear and loading characteristics. Individual plots of surface roughness, diameter variations, feeding forces, cutting horsepower, and spindle speeds for each material are summarized in Figs. 1 through 24. A comparison of the results indicates that the "T" materials, as a rule, did not behave as well as the others. They gave rise, generally, to greater tool wear, higher feeding forces, and higher power requirements Surface quality, on the other hand, was comparable for all tools and in many cases was even better on the T materials, although not as many parts were produced. Of the eleven runs made on the ten materials (including a rerun on T3), only materials A and 122 ran for 20 bars -approximately 200 pieces —without stalling the machine. Material 122 gave the better overall results. 2

The three standard materials, A, G, and T2, showed differences in behavior, but the differences were not consistent. Material A, for example, permitted the longest run but produced the poorest surface quality; material T2 gave the best overall surface quality in spite of greater tool wear for 73% as many parts; material G had the most uniform surface quality, appeared to promote less tool wear, but required more power for forming and drilling, and produced only 64% as many pieces before stalling the machine. Additional observations are made in the brief summaries covering each operation. LIGHT-FORMING Figures l.through 7 and Figs. 13 and 14 represent the results of the lightforming operation on the oxide and inner surfaces. Light-forming on the inner surface produced the most consistent surface quality among all materials, although the materials can be grouped into two surface-behavior patterns. One group-materials T1 through T —showed an improving surface quality in the early stages of a run until stable values were reached. The other materials started out with good surfaces which were maintained throughout the entire range of pieces produced with only slight increases in roughness. Light-forming of the oxide surface produced much more erratic behavior, and in all but two cases resulted in much higher average surface roughness and feeding force values, even though the initial values were very similar to those produced on the inner surface. The difference in average levels can be attributed mainly to the higher rate of tool wear in this operation. It is interesting to note that the average surface quality of the T materials, with the exception of T3, is as good or better than the average surface quality of the other materials even though the tool wear was as much as 250% higher. More burnishing was evident, however, on those materials, which gave rise to greater tool wear. Materials T2 and 221, with emulsion, gave the best average surface quality, comparable to that produced on the inner surface in each case, The effect of the oxide on the 221 material was more pronounced, however, when oil was used as the cutting fluid. The surface roughness more than doubled early in the run. The generally poor results shown by materials T3 and T4 must, in some way, be attributed to the centerless grinding operation during fabrication. Apparently, not only the sequence of grinding is important, but the process itself appears to be undesirable because it contributes to a surface condition which promotes rough tool wear and gives rise to the poor results. In comparison with material T4, material T3, which was ground after heat treatment and before colddrawing, had the most rapid changes in surface quality, dimensional stability, and feeding forces on the oxide surface, and gave an equivalent amount of tool wear for only half as many parts. Material T4, which was ground before heat treatment, had the most erratic behavior on the oxide surface as well as the greatest diameter variations on the inner surface among all materials. The original bar surfaces were examined under a binocular microscope and compared 3

with other bar surfaces, but no noticeable differences in appearance were notedo Several reasons could be given for the poor behavior of the ground materials, but further studies would have to be made to establish the cause definitely. HEAVY-FORMING The heavy-forming surface-roughness results are shown in Figs. 1 through 5. In general, those materials which gave poor and erratic surface quality in light-forming of the oxide surface also behaved badly in heavy-forming. In most cases, the surface got progressively worse with the number of pieces produced, with materials A, 122, 221 oil, and T3 showing the greatest variations Some of the surface-roughness results, as measured with the profilometer, are rather misleading if taken entirely at their face value, for the profilometer does not always reveal the true character of a surface. It may be noted in Figs. 1 through 5 that some of the materials show an increasing surface roughness to a maximum, beyond which the surface appears to improve. Visual inspection, however, reveals that in practically all cases the sharp changes in surface roughness, predicted by the profilometer, were accompanied by the appearance of burnished rings, and that the burnishing became progressively worse as the test continued even though the surface-roughness values may have dropped. On some of the materials the burnished rings appeared after only a few hundred pieces, and only the surfaces of materials G and 122 appeared good throughout most of the run. These materials gave rise to the lowest feeding forces, On the other hand, material T2 had the best average surface quality as recorded by the profilometer, but the visual appearance was inferior when compared with the surface produced on material G, for example. It was better than that produced on material A, however. There did not appear to be a consistent relationship between tool wear and surface quality, For example, materials, G, Ti, and T5 had the same surface roughness but the tool wear was.0029 in,,.0107 in,, and.0051 in,, respectively. To and T5 produced about the same number of pieces, while 40% more pieces were produced from material Go Tool wear had much more effect upon dimensional stability and feeding forces, Figures 8 and 9, Figs, 15 and 16, and Tables II and III show these effects, In general, the greater the tool wear the higher the feeding forces, and the greater the variations in formed diameter. There were, however, some differences in behavior among the various materials. For example, T6 gave rise to.0081-in, wear on the form tool, requiring a maximum feeding force of 505 lb. Material A, however, required a maximum feeding force of only 180 lb for the same amount of wear, even though the initial (sharp tool) force was 45% higher than the initial force recorded for the T6 material, 11

TABLE II SUMMARY OF TOOL WEAR, DIAMETER VARIATIONS, AND FEEDING FORCES FOR HEAVY-FORMING OPERATION Tool Wear, Diameter Range, Feeding Force Material No. of Pieces i Range lb in. ino Range, Ib A 2457 0086 00276 16-180 G 1577.0029 0143 34-86 122 2451 o0050 0135 26-54 221 Oil 1964.0105 00368 23-399 221 Em 1218.0033 00172 21-116 TL 1207.0107.0488 34-414 T2 1793.0098 o0445 17-286 T3 1033.0093.0344 21-315 T4 2080 o0090 0445 15-253 T5 1194.0051.0200 26-177 T6 2002.0084 00496 11-505 These discrepancies in forces can be accounted for, at least partly by the condition of the cutting toolo Although two tools may have similar flank-wear values, one wear pattern may show much more severe breakdown of the contact area than the other. Rough wear was typical of the T materials. The differences are noted in Tables IV and Vo A very small part of the increase or growth in diameter is a result of the actual wearing away of the flank, but the greatest change, by far, is due to the deflections in machine components brought about by the increased feeding forces. As mentioned previously, the forces had little, if any effect upon measured surface roughness, although burnishing was less pronounced when the forces were smaller. TURNING ~The turned-surface quality and the diameter and feeding-force variations are shown in FigSo 1 through 5, and Figs. 10 through 12, respectively. With the exception of materials 221 oil and emulsion, T3, and T4, which gave very erratic results not only in measured values but in appearance, the turned-surface quality was fairly consistent throughout the runs on most of the materials, although there were some differences in levels as recorded by the profilometero Materials G and T1 gave excellent turned surface quality. The use of oil as a cutting fluid on the 221 material produced a reversal 1 surface-finish behaovior. W-ith em7ulsionr, the surface quality, though poor, 3

followed a trend similar to that displayed by most of the other materials: it improved with the number of pieces producedo With oil, however, the surface was generally bad and highly burnished, and got worse as the run progressed, Loss of dimensional stability was more pronounced on the T materials, with material T3 showing a growth in turned diameter of o008 in. in 1033 pieceso Tool wear and tool feeding forces were generally higher, and undoubtedly account for the rapid loss in accuracy. Materials A, G, 122, and 221 had the most consistent forces throughout the run, but the turned diameters were erratic even though there was no rapid growth in size. Some differences in behavior from one bar to the next were noted on material A, and this may account for the very pronounced turned-diameter variations between 500 and 1000 pieceso DRILLING In general, drilling performance was one of the important factors in determining the number of parts which could be produced before stalling of the machine occurred. This is discussed more fully in the section on Spindle Speedsiand Power. The only other recorded results-drilling thrust —are shown plotted in Figs. 17 and 18. The results show a considerable range in thrust-force behavior. Generally speaking, the initial thrust-force values were similar among the T materials, but the behavior patterns differed rather extensively. Material T2 showed the most rapid and most drastic change in thrust force, rising from an initial value of approximately 180 lb to over 600 lb in a range of 200 pieces. The erratic force behavior on the T materials is undoubtedly associated with drill wear, for as can be noted in Tables IV and V, the wear was more severe on these materials, particularly with respect to corner and edge breakdown, The two materials that ran for 20 bars, A and 122, had the lowest and most consistent thrust forces. The forces rose only 40 and 60%, respectively, in 2450 pieceso This compares with an increase of 285% in 1790 pieces on material T2. Drill corner damage was much more severe on the latter material, however. On the other hand, material G, which actually showed the least severe drill wear, had the highest initial thrust forces. These were almost three times as high as those on the other materials, although there was an increase in force of only 30% in 1575 pieces. Formal measurements of drilled-hole diameters and of surface roughness were not made, but random checks along with visual inspection of the surfaces did show some minor differences among the various materials, particularly in surface-finish behavior. Hole size was quite good and was fairly consistent from one material to the next with the exception of the early stages of the run on material Ao Excessively oversize holes were produced for the first several hundred pieces before good dimensional stability was reached, 9

The drilled surface qualtiy was not exceptional on any of the materials. Material G had the best and most consistent surface over the entire range of parts, while material 122 had a rather rough and torn surface from beginning to end. Most of the other materials started out with fair to good surfaces in the beginning which got progressively worse as the run continued. The use of oil on material 221 produced a highly burnished surface in contrast to a dull, fairly rough surface produced with the emulsion. REAMING No formal measurements were made of the reaming operation. Feeding forces were recorded, but the changes, if any, were so small that they were difficult to pick up. Like the drilled holes, the reamed holes in material A were oversize in the beginning of the run but improved with the number of pieces. All other materials produced holes which were tight on the reamers during spot checks for size. Surface-finish behavior was, in some respects, just opposite to that shown in drilling. Material 122, which gave poor drilled surface quality, gave a good and a consistent reamed finish throughout the run of parts. Also, the materials which showed a continuous decrease in drilled surface quality exhibited just the reverse in reaming. The reamed surface improved as the number of pieces increased. Material G,which had the best and most consistent drilled finish, was very erratic in reaming and did not show as good a surface as most of the other materials. The reamers were inspected for wear, but no significant differences were found among the results. Generally, only some rounding of the chamfered corners was noted. CUTOFF Outside of measurements of tool wear, the only observations of the cutoff operation were made visually. As may be seen in Tables IV and V, tool wear was most severe on the T materials, with much more pronounced edge and corner breakdown. The surface quality was similar in appearance among all materials, although there were slight differences in behavior. With the exception of 221 emulsion and T2, all materials produced fair to good surfaces in the beginning. However, these surfaces got worse as the runs progressed and then began to improve near the end. The cutoff surfaces on material 221 emulsion and T2 were consistently bad throughout the range of parts produced. 10

SPINDLLE SPEEDS AND POWER The curves plotted in FigSo 19 through 24 represent the horsepower rem quirements and the spindle speeds as they change with tool wear on two critical operations-drilling and formingo Turning horsepower is also plotted in Figs. 19 through 21. The drilling results represent the values of horsepower and spindle speed at the point where the drill has just reached the full length of the hole, or, in the case of forming, the results represent the horsepower and spindle speed during heavy-forming to sizeo The drilling results are of particular interest, since this operation contributed most to the stalling of the machine on the short runs Drilling behavior fell into two general categories. In one case, the drilling horsepower increased as the length of the hole increased, while in the other there was little, if any, increase in power from the start to the end of the drilling operation. Most of the materials fell somewhere in between these two extremes Materials A and 122 required the least power and had the lowest rate of increase. Material A was also the only material which required less horsepower for drilling than for forming under the given cutting conditions Both of these materials ran for the full test of 20 barso To illustrate differences in material behavior, a fourth power curve is plotted in Figo 19 for material T1 and in Fig. 20 for material A. In addition actual traces of the power curves as recorded by the wattmeter are shown in Figo 28. The extra curve in FigSo 19 and 20 represents the power consumed during a combination cut including the beginning of drilling and partial formingo Therefore, the horsepower for the combination cut should be greater than the horsepower for the end of drilling as long as there is no great increase in drilling power requirements with an increase in hole lengtho It may be noted in Figs. 20 and 28, that, for material A, the end of drilling horsepower is lower than the horsepower for the combination cut over the entire range of partso This was also a typical pattern on materialc 122 and T6. The speed curves in Figso 23 and 24 also substantiate that drilling was less critical on these materials, because the greatest drop in speed was contributed by the combined cut. (Materials A and 122 have a speed curve plotted only for that operation which contributed most to spindle speed slowdowno) The power and speed curves for material T1 in Figso 19 and 22, and the wattmeter traces in Figo 28, represent the second type of behavior into which most of the materials fell. Initially the end of drilling horsepower was lower than the horsepower for the combined cuto However, as the test progressed, the drilling horsepower increased more and more with the length of the hole until the end of drilling horsepower was greater than that required for the combined cut at the start of the hole. The speed curves illustrate the same type of behavior Whether the changes occurred as a result of tool wear or whether they occurred as a result of residual stresses (Table VII) induced during fabrication or by the form tools requires further study, In any 11

event, the increase in horsepower, coupled with the drive-motor characteristics, was sufficient either to stall the machine, or to slow it down so much that continued running was inpractical. CHIP FORMATION The chip ratings given in Table VI are based upon arbitrary ratings assigned to chips of certain shape and size as described at the bottom of the table. The ratings given for every fifth bar are average values for the combined chips from all operations and should indicate the changes in behavior as tool wear increases. The composite rating for the material is an average of the individual bar ratings. By far the best chips were produced from material G. All the chips were very finely broken up and usually of one coil or less in length. Most of the other materials had at least some tendency for long or stringy chips in drilling, turning, or cutoff. The forming chips were usually not troublesome. RESIDUAL STRESSES IN MACHINED PARTS Table VII is included in this report to indicate not only that residual stresses exist in the machined parts, but also that they can be either predominantly compressive or tensile in nature. No definite conclusions can be based upon this information, for the stress studies are far from complete. Additional work would be required before any real value can be placed upon the results, but it is believed that these stresses do have at least some significance in the machinability ratings of the various materials. The values in Table VII represent the difference between two scribed gage marks before and after axial and radial sawing of the two rings representing the light-formed and heavy-formed surfaces on the machined part. Some of the values are negative, indicating a closing of the part, while the positive values indicate that the rings opened up after sawing. The distribution of stresses is not known, however. TRACES OF FEEDING AND THRUST FORCES Figures 25, 26, and 27 show actual traces of the feeding forces on the turn and form tools, and drilling thrust. They serve to illustrate the changes that take place during a run, as well as the differences in behavior among the various materials. The effects of surface oxides can also be noted, particularly in the light-forming operationo 12

TABLE VI CHIP-FORMATION SUMMARY Chip Ratings by Number of Bars* (120 pcs/bar) Material Overall Bar No. 1, Bar No, 5, Bar Noo 10, Bar No. 15, Bar No. 20, Rating, _ l. I.o A 80 85 95 95 90 89 G 120 120 120 120 122 95 90 95 100 105 97 221 Oil 95 100 105 105 101 221 Em. 100 90 85 92 T1 9 90 100 95 T2 90 80 60 77 T3 85 80 82 T4 85 95 65 81 T5 85 90 80 85 T6 70 95 65 70 75 Chip Ratings More than 100% - very fine and well-broken chips. 100% - tight coils to 1 in. long - very short open coils. 80% - tight coils to 6 in. long - short open coils to 3 in. long - very short loose coils - minor nuisance. 60% - tight coils to 12 in. long - open coils to 6 in. long - large loose coils to 3 in. long - moderate nuisance. Less than 60% - very long tight coils - long open coils and stringy balledup chips - major nuisance. 13

TABLE VII RESIDUAL STRESSES IN TEST PARTS ON BASIS OF DEFORMATION AFTER AXIAL AND RADIAL SLOTTING Saw cuts Original Gge width gage lines A B Gage width.200 in. apart after slotting Deformation equals B-A. Negative values indicate closing of part. Light-Forming Heavy-Forming Material, First Last First Last IDifference Difference pieces Piece Piece Piece Piece. B-A, in. B-A, in. B-A, in. B-A, in. A, 2457.0043.0105.0062.0033.0043.0010 G, 1577.0052.0109.0057.0016.0092.0075 122, 2451.0013 o0029.0016.0014 -.0063 -.0077 221 Oil, 1964.0004.0070.0066.0010 -.0092 -.0102 221 Em, 1218.0028.0121.0093.0053.0119.0066 T1, 1207.0010.0236.0226.0002.0044.0042 T2, 1793.0004.0184.0180 -.0010.0180.0190 T3, 1033 o0016.0252.0236.0018.0257.0239 T4, 2080.0034 -.0090 -.0124.0032.0106.0074 Ts, 1194.0002.0148.0146.0020.0154.0134 T6, 2002.0018.0050.2.0022 -.0076 -.0098 14

MATERIAL G MATERIAL A 60 60 TURNING. 40 40: == C LIGHT FORMING z 1 40 40o I__ INNER SURFACE o...............' 2................. 20 20 - | I~~~ I:~LIGHT FORMING L,,. 60 60 la z OXIDE SURFACE I0I; =44 40 20 20 U) HEAVY FORMING - 40 40- ~\ 500_100_NUMBE 2O P0 500 10 00 NUMBER OF PIECES 500 1000 1500 2000 2500 Fig. i. Divisions for number of pieces under turning and light-forming.

MATERIAL T2 MATERIAL 122 TURNING 40 40 w 20 20 I lLIGHT FORMING -INNER SURFACE I: r = |UGHT FORMING - OXODE SURFACE i_ - 4~40 40 or 20 200 0 -40..................... 20 3-....C __ _ _ =:..0~ UGHT~ EAVY FOR MING - XE SURFACE L 0> /=220 500 1000 NUMBER OF PIECES 500 1000 1500 2000 2500 Fig. 3. Divisions for number of pieces under turning and light-forming.

MATERIAL TI MATERIAL T3 MATERIAL T4 80 80 TURNING ^' TU RNING N 4 -4 0......... TURNING m 2OF 20 LIGHT FORMING LIGHT FORMING INNR SUFACE LIGHT FORMING INNER SURFACE':'-:,:,:: 120= 20.. INN ~._.~:,.~.~ER SURFACE 40,,............................................... INNER.,,. SURFACE:;.,:;,,......... la.I P.-,-~*-.....:-"'~~~~~~"'.......: to | LIGHT FORMING 60 60 OXIDE SURFACE LIGHT FORMING OXIDE SURFACE 40m LIGHT FORMING. |20 2.OXi.DE SURFACE. 20 0 1020 0 500 1000?. 2000 Fig. 4. Divisions for number of pieces under -turning anda light-forming. HEAVY FORMING HEAVY FORMING ( HEAVY FORMING 40 40...... 24<........... 0 500 I 000 500 1000 5O0 I000 1500 1 O0 NUMBER OF PIECES Fig. 4. Divisions for number of pieces under turning and light-forming.

MATERIAL T5 MATERIAL T6 TURNING 60 60 40 t 1 40 LIGHT FORMING 2.0 20 20 LIGHT FORMING 2z- 40 INNER SURFACE 40 0 O I2Q~, 1 20 i20' 20.............-........~I_~.. LIGHT FORMING C) 60- OXIDE SURFACE 60O40 - 40^oI I I__ __ _ 20 0 2000 F. HEAVY FORMING 60 - 60co 40o- 40 - 201 20 0 500 1000 NUMBER OF PIECES 0 500 1000 1500 2000 Fig. 5. Divisions for number of pieces under turning and light-forming.

2 E~ 33 MATERIAL 4 A MATERIAL 6 ~~ MINNER SURFACE -, ~ OXIDE SURFACE ^ / \A _ I &9 2.0,'e- ^^'^/^V ~,^ ^ ~OXIDE SUSRFACE MATERIAL 1Z2 &-~ -Q~ INNER SURFACE W O g. 20 ~ -*~- OXIDE SURFACE 0 ~ ^ L rJ~~~~~~~~~M E1. Z 5^^! ^ f ^/\ ~ ^~ff SURFACEURFAC ^u // ~"INNER SUROXIDE SUA RFXIE URAC WI Ow 0 500 1000 1500 2000 2500 NUMBER OF PIECES MATERIgAL 22 -EMih-omnULSONMARIAL 221 - OIL INNER SURF.ACE J - INNER SURFACE OXIDE SURFACE " 2 - OXIDE SURFACE 2 -W Uj~~~~~~~ a: A 0 500 1000 1500 2000 2500 0 500 1000 1500 2000 NUMBER OF PIECES NUMBER OF PIECES Fig. 6. Light-forming diameter variations vs. number of pieces.

3 3 11V^~~~~~~~~NNER SURFACE MATERIAL A MATERIAL -- OXIDE SURFACE M I -' - NNER SURFACE I N. A: *, OXIDE SURFACE V 0^" \ \ MAERI/AL TJ3 MATERIAL r4,' ~INNER SURFACEFACE ((J lb^f a. \ " i I,: a Z' /INNER SURFACE 3 - N SR g_2;,, -— OXIDE SURFACE OI F 2 2 r o r~~~ t o I NUMBER OF PIECES NUMBER SUOF PIECES r' //

36 - 36-.32 32 5 28- MATERIALS A, G, AND 122 28- MATERIAL 221 2_ 24 - 2W A OIL:, 20- 20 ro -- I G EM —-—../ 4 - 4 PP 12 12 Iwl;', 4 4 - I _500 1000 1500 2000 2500 0 / 500. oo1 000 15 00_I o 560s 1000 1500 2000 2500 0 500 00' 0 1500 2000 NUMBER OF PIECES Fig. 8. Heavy-forming d.iamneter variations vs. number of pieces.

52'MATERIALS TI, T2, T3, AND T4. MATERIALS Tg AND Tg 48- 4844'\ 44 40- 40 " -I I o, /3 32 /^ / f 32 28-8 u- 28 w /4 20 T. /' 20 / - W.l,.2 16 /, 1 8 12 /12 8 - / 8 4- 4 / ( ~58~500 1000 ~15 00 2000 0 500 M100 1500 2000 NUMBER OF PIECES NUMBER OF PIE CE Fig. 9. Heavy-forming diameter variations vs. number of pieces.

_j CO 001 60 z G -I t~~~~~~~~ 0) 40 40 EMULSION 500 1000 1500 2000 2500 500 1000 1500 2000 MATERIALS A AND G MATERIAL 221 -EMULSION AND OIL 8- hii..P-~~ 7-A. Be- I \_, ~^ (~ i t teJ' I' * w 4I &z~~~~~~'I'* r\ ~~~~~~~OIL % it I I_ ~ 3 ~~ i i 3 w jj V i, ^v M /^" ^\\/ v ^, \ ^^v ^^ ^~~~~~~~~~~~'1*i~ SCI~~ -^/ ^ G I~EMULSION o 500 1000 1500 2000 2500 0 500 1000 1500 2000 NUMBER OF PIECES Fig. 10. Turning (i2eter and feeding-force variations vs. number of pieces.

Ci 0 io 65- 1100- 5 TL M T AND TA ~~~~~~~~~~MATERIALS T AND T2 I \ 0 7 -T, o T' 3 -- 4.._. T.6- 6- I' teJ' 1O^'~ ^~ ~ ~'/ /!4, ~^ 4_~ 3- 3-,,, U' 0 500 1000 1500 0 500 1000 1500 2000 NUMBER OF PIECES Fig. 11. Turning diameter and feeding-force variations vs. number of ieces.

200 -160 - w12 80,,,40t ZO Lo _ w 20 I& I ____I I I__I_ I_~ I I 1 _____I ____~I__________II __________ _I-_____________I___________ __, 500 1000 1500 2000 00 1000 1500 2000 2500 MATERIALS t5 AND _~^~~~~ r ~T^~6 ~ MATERIAL 122 O 8 " 4 04 z A,/ / 6- 3 1 ie / \' I /^ 0 A/ - V P 500 1000 1500 2000 0 500 1000 1500 2000 2500 NUMBER OF PIECES Fig. 12. Turning diameter and feeding-force variations vs. number of pieces.

40 40 MATERIAL 6 3. MATERIAL A INNER SURFACE w~ ---- OXIDE SURFACE 30 ~r, e' AA ^~ 20C ^^^ ^ S ~ ~ ^^ ~z~~~~~ ~~ I../NNER SURFACE ao 1,, 10 —, OXIDE SURFACE ~^ 5j 30' 3 MATZ RIAL 122 I z 10~ -/LINE/ SURFAE o OXIDE SURFACE NUMBER OF PIECES m 400 —-MATERIAL 221 - EMULSION MATL ERIAL 221- O/L' ______ /^^^ eiio ~ ^INNAR SURFACE /INNER. SURFACE - OX/DE SURFACE r 20 am OXIDE SURFACE 2 ~~~~~~~~0 A~20 o~___1____0 0oI__ I _' 1 I ______ 0 500 1000 1500 0 500 1000 1500 2000 NUMBER OF PIECES NUMBER OF PIECES Fig. 13. Light-forming feeding forces vs. number of pieces.

MATERIAL Tf MATERIAL 7T 40- l 40 mS'30 * 30w; ~ INNER SURFACE ~It8~~ a~~~^x.'^~ ~~.~ -— OXIDE SURFACE~20, 20lO- ~ /INNER SURFACE W -- OXIDE SURFACE o, I I o lI I, MATERAL T MATERIAL T4 -30 30 ~. 20, v 2- INNER SURFACE zI0 e ~,/ INNER SURFACE — OXIDE SURFACE.', s 5 10- ---- OXIDE SURFACE o "-o, 0 I, I, I 40 MATER/AL T5 4 MATERIAL 76 40 5 40 30 30 INI NEt SURFA CE 30IN/NNER SURFACE 3 INNER SURFACE'' 20 ~ /OXIDE SURFACE E S I O 20 120 - o 0 ~_. I I,I 0 500 1000 1500 0 500 1000 1500 2000 NUMBER OF PIECES NUMBER OF PIECES Fig. 14. Light-forming feeding forces vs. number of pieces.

MATERIAL 221 - 400- EMULSION AND OIL 360 OIL 320 o 280 2 0 MATERIALS A, G, AND 122 240 200^^so\ Ay n~/y -160 ze 12/^ ^ ~ 122`'-120 W. so G t, ~~~~~~~~~~~~~~~~~~~~~~~~~80 I ________2^ ^ ^ ^ EMULSION j/~~~~~~~~~~~~~~~~~(~~~~~~~~~~~~4~~~~~ ^^T.~/7^-.^ ^ \-^^ ~~40^^T ____ _________________I_________I_________________i_________ II_____!___ 0 500 1000 1500 2000 2500 0 500 1000 1500 2000 NUMBER OF PIECES Fig. 15. Heavy-forming feeding forces vs. number of pieces.

520 520 480 480 440 MATERIALS Ti, T2, T3, AND. T4 440 400- l 400 MATERIALS T5 AND T 360 360 a 320 1- 320 z 280 T 280- T3 240 / 240 1' 200 200 Fig. 16. Hy-fi4 160 - I/ - - 0 500 1000 1500 2000 0 500 1000 1500 2000 NUMBER OF PIECES Fig. 16. Heavy-forming feeding forces vs. number of pieces.

680 640- / ^ 600 560 520 520 co~~~~~~~~~~~* -J 480 480 IL I tI *8 A co 0 I1 0:440 33 9' J1 U 44-'\ 0' * I ~* ~ D 400-I 400 I i Cr~~~~~~~~ 0 \ Q= g i C') 360 a 360e 280 -^^280-; JI -"^ I ^A,' ^ MATERIALS 7J AND T4 * 3 6 320 020 16280 160 500 1000 1500 2000 0 500 1000 1500 NUMBER OF PIECES NUMBER OF PIECES Fig. 17- Drilling~-thrus forces vs. number of pieces.

680 660 - 620 6 A580h / 540 \ MArERIALS- Tr, T6, AND /2 500 0 I MATERIALS A,, G AND 221 460 I 460 w 420 4 2420 I' U: b..-o —-T5 I, 340 340 " 300 300 260 7- 26 /, \.\: ~ w/ ~ Z~I'/\ ^ /^^ /^ / " ^^221EMULSION 200 / 220 180 2 180 140 140 500 1000 1500 2000 500 1000 1500 2000 2500 NUMBER OF PIECES NUMBER OF PIECES Fig. 18. Drilling-thrust forces vs. number of pieces.

MATERIAL T71 ~ DRILLING FORMING ~TURNING.0 CL z cn 2.5r cc 00c ^ 2.0 \^f ~ DRILLING Z *.~ lL^^' lIYI~IIPORIGL MATERIAL T2 c -— ^* ^ ~ -— COMBINED DRILL a FORM' 15 ^ ~ * ~~~TURNING 1.0 DRILLING DRILLING FORMING FORMING TURNING a- 3.5 TURNING w MATERIAL TM 3:~~~~~~~~~' ^, ~~~~~~~~~~ ~ ~~~~~~~~MATER'tAL; ^ 0 a.3.0 - / Im ^i' r 0 2.5- /-\ ^/ I I I I Z 2.00 500 1000 1500 2000 500 1000 1500 2000 NUMBER OF PIECES NUMBER OF PIECES Fig. 19. Cutting horsepower vs. number of pieces.

DRILLING HP 35 DRILLING HP. ------ FORMING HP _ -~- TURNING HR TURNING HP w -. -. FORMING HP s 25 MATERIAL T6 1 | C DL~ MA/T/RAL 7T -- - T/ 2_0 FI> t)~I, GDRLLING HP. ~ DRILLN H~ DRILLING HP. ~, F —- FORIFORMING HHP 500....TURNING HP. 3.5 _ ~ I~lbdr nCOMBINED DRILLING a FORMING HP TURNING HR ~ TURNING HMAR/L G 1: MAT ERIAL G w 3.00 a. MATERIAL A d W Fig. 20. Cutting horsepower vs. number of pieces. 500 1000 1500 2000 0 500 1000 1500 2000 2500 NUMBER OF PIECES NUMBER OF PIECES Fig. 20. Cutting horsepower vs. number of pieces.

3,5 g MATERIAL - 122 DRI LING HP 3^ 3.0 -N -- - FORMING HP O0 -- -~ TURNING HP?_0 2.5 - 21.0 MATERIA L - 221 - E r3.5 3.5 MATERIAL- 221 -OIL w LL o 3.0 30 Lt,5 V) ulp2.5 0.o 0'" UJ NUMBER OF PIECES NU.5MBER OF PIE Fig. 21. Cutting horsepower vs. number of pieces. o 2.0 - \^ " o 2.0 B1 I i1 1. 1 500 1000 1500 2000 0 500 1000 1500 2000 NUMBER OF PIECES NUMBER OF PIECES Fig. 21. Cutting horsepower vs. number of pieces.

IDLE RPM =~490 IDLE RPM= Z490 2400 2 100 1950:IW. MAsERAo.A 1800 ~' 1650 It i -DO b - ~ /LL a FORM 1j - END OF DRILUNS 2 1-350 - - - IO FORMING Q 1200 - ~ — R/LL B FORM 1050 - END OF DRILLING 900 -- - — Io FORMING 1 i I.I 1 1. IDLE RPM N2490 IDLE RPM'2490 ~., 2400- - MATERIAL T, 2250 MATERIAL T. 2 2100A "boa 1950 * S 1200,* EN~D OF DRLLING 0-O FORFMING ING -1050 ~ - -6 FORMING 900- - I IRI8 FORMI 1 1M 0 500 1000 1500 2000 0 500 1000 1500 2000 NUMBER OF PIECES NUMBER OF PIECES Fig. 22. Spindle rpm vs. number of pieces.

IDLE RPM —2490 - IDLE RPM 2490 2400 _ 2250o L MATERIAL T. MrEmAL r 195010- - 9100 _ I15 COMBINED DRILL B FORM 13250 -- -- F END OF DRILLING.l12ioot u FORMING ~ v — oo w nn-m ~ COMB/NED DRILL AN FORM RM 9500 IDLE PM 2490 IDLE RPM 2490 n 2400 ~ —RMIN I0 ^0 —-O COMBINED DRILL AND FORM "1650 90go0Q _ **-4 END OF DRILLING 0 500 1000 1500 2000 0 500 1000 1500 2000 NUMBER OF PIECES NUMBER OF PIECES Fig. 23. Spindle rpm vs. number of pieces.

IDLE RPM 24 90 I _DLE RPM _ 2490 _ 2400 MATERIAL- 221-0 2250 MATERIAL- 221-EM __ 2100 H - -_ \ 1950 _.,1650 m1500 1000 1500 2000 /D~f RPM END OF DRIL_ NUMBER OF PIECES M -1200 0 21950 _ o'',, 1800 — OICOMBINED DRLL FORM NGRM CL, C I D165015001 1050 900 o~~~~0 500 1000l 1500 00 2500 -.......NUMBER OF PIECES Fig. 2 Spindle r vs. nber of peces. o. 21 - o o 1650 w 1500 o 135 c1050 0 500 I000 1500 2000 NUMBER OF PIECES Fig. 24. Spindle rpm vs. number of pieces.

Material - T1 - 1207 pieces Trace of; force on Trace of force.-.: oxide:i: on inner sur- 4 -, surface. I_ face.': Beginning, ATT-2X End, ATT-2X Material - T2 - 1793 pieces.:.~t i " -~~i Beginning, ATT-1X 1000 pcs., ATT-lX End, ATT-lX 1.1.. I "''~': I. ^ 1". - 1.;..-....-.:...i"":. i....... l:::i'5;^,,','::':.':: T:: ll'lp0 s i i i i' i ]i.. 1 -i -{ ".........!..:.i -- - i 5l l. ~-l - l-.:..~................~ I4.:: {. -~~ i'.....'...................... BeBeginning, ATT-lX 4160 pcs., ATT-X 8 p. End, ATT-1X Material - T4 - 2080 pieces. F~,:ii~~~~~~~~~~~~~~~~~~.^^~ ~~~~ ~5~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~-.:..............,. a -j.';- - ~.i'~'b^ i ^1^ -I' 1 I v4 1 } Hl- \ > y ~ ~ ~ ~:.~... —. —~-.^...' 11-1.- ^l~~;~il~~~I —i; * -: - - _... ~i,:,,' I'. ~' ~ r ~, ~ i ~'~ - s''~ i''. ~.;'.i....:1 * i; ~...... -?.......... Beginning, ATT-iX 1650 pcs., ATT-iX End, ATT-lX Fig. 25. Light-forming traces of feeding forces on oxide and inner surfaces. Forces are traced from left to right. 59

Material - T5 - 1194 pieces Beginning, ATT-lX 900 pcs., ATT-lX 1100 pcs., ATT-1X End, ATT-1X Material - Tg - 2002 pieces j f I I:I I Beginning, ATT-X 180 0 pc s. ATT -X 00 End, ATT- 1X Material - Temulsion 200218 pieces llll l ll:" t:.:',''t i Beginning, ATT-1X 180 pcs., ATT-1X En, ATT-TTMaterial - 221 emulsion - 1218 pieces';'i;".:.::'::.:X:".~.~i!~:J:::'::::.;':.:i'.':'.'.J:...i::.',!.!..":.!'..:'.''d? "i "/"i' -'' Fig. 2... Con..tinued. 40 Material - 6 221 2oil 0-21 pieces r: -ti~rI' D' a:i~::;-:'. ~~-I- -:D..e tE ->....i:~.......:............. ~::i:~:i~.;..:-I;~'''''::-ii:::' -::'::i'::~~ii-:; ~~~~~;~: ~ ~;.:..v'-E.'..,E: l.t:".'::':#:': Beginning, ATT-lX 1850 pEc.,d, TlX E,,.,0 ATT * s:S — o~s- o............... ^ J X~tN.8.v.. ff |E;;'::........ c,.'., t-:.'q. i;.;..::;::':::::q, ~:- ~ ~ Fg 25. Continued. —:-~~ ~~~~~~i~r~~::::::i::l::::::~'-'::~i ~~::i ~; ~:::I ii4 0::::

Material - G - 1577 pieces::': l::?::M,::'i.::":::;:;:::'::""'i: "::':'. ~ Beginning, ATT-1X 450 pcs., ATT-2X End, ATT-2X Material - A - 2457 pieces:|::.i:.s::'':::: -— ^ ^ ^^~7~:i ~ -~^ -:-:-~ ii: -i~~~iir~~i..+ r^ ^ ~n~~..tl 5 ^::::;~.'':'';~^;~::~::il:~'_il':~' ":: it' o | i 5ji;..i.':.j~~lj::i'~:.~- ~ ~:i~:~.:::..'......} ATT-lX ATT-1X ATT-lX ATT-iX Material - 122 - 2451 pieces * E f g s*: k...... _ ^ -! -..........:...: ~m 3 i;. i:;;:1.....-T:';~;::.:l.;'::2::::.....:.....;!.! Beginning 650 pcs. End ATT-1X ATT-IX ATT-1X'4.'

Material - T1 - 1207 pieces Trace of [................ Trace of...........'" Trace of forces' forces for for partial i. finish cutoff and' Yi cutoff and. } finish fr partial form finish form __~^..^ j...:;.-....p.;... ~ ~..l^.l I; fc: -^.1.4:-l;^...',Z..:.. $fr~~~~~~ Beginning, ATT-2X End, ATT-10X Material - T2 - 1793 pieces "'.!{.'..:..!....'''}''" "~"/ i""';"'i'': i"~:'~'~.l.lll!:.l lll.......St m:. H'1 -.' p ^ T;;~:.~~:...;:- ^I~ ~ ~''R R~''j"''^H 1^ Beginning, ATT-1X 1150 pcs., A'IT-~-OX End., ATT-20X Material - T3 - 1033 pieces.71 ~ ~ ~ ~ ~ NK t iA... ^~ ~~...........a.^llulTi.r:i:jii:.~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~..........:...........~..:. yftU.i'I ^ h-" ^& "^&. & & 11^ r' IT":.'^ ^~i~"^.I.;I..;HTH.1 l~~~~~~~~~~~~~~~~~~~~i~~i ~T^I~'n~'~.H~~~~~l~. ~.~.OJ.~~~..~ht.^:.t;. ^" j~~~~~~~~~~l.;.;;I............ Beginning, ATT-2X 160 pcs., ATT-5X End., ATT-10X Material -T^ 2080 pieces Fig. 26. Heavy-forming traces of feeding forces. Forces are traced, from left to right. 42

Material - T5 1194 pieces ~~~:i.- m ~ ~:t:' -.v ^::... ~.............. ^' ^.;'.IF'.~...-j.....J.."':j^>~l^~^:....~ll...: i': i'': I ii i iiif i nini n'"'^i' j~~~~~~~' ~'~ i'.ii~i'[i:]'!? ~111['i''11'![[[ii!gfli^~ Beginning, ATT-2X End, ATT-5X Material - T - 2002 pieces Bgning, ATT-2X 1850 pcs., ATT-10X End.,AT-0 Material 221 emulsion 1218 pieces ~ 1 ^ rr'1 - r l~~l -; ~t -: ~~~~l: ~ - I;...........:.;:.; n -: r..'.: I T:....-! -; - 4. <1 ft UT?~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~.... Beginning, ~ ~ ~ ^",^'^^^"~' ATT-2Xl:lr 185 pcs. ATT lox End ATT-lOX —— ~T*I........ Beginning, ATT lX End, ATT-5X Material 221 oil -1964 p iec e s. E- ATT-ll i lX l~~~l~~iillJ.:Blj~~~~~~~~~ijll~~~~lj^... lillllii~~~~~~~~~~~~lLL.^.ll~~~~~~~jlli.L:^ lllllu-ll~~~~~~~~~~~~~~l~~~i~~llliJ~~~~~l..y........l..... Beginning, ATT-2X 1800 pcs.., ATT-5OX Endpc. ATT-lOX Fig~~....._.....__^^. 26..^:...... Conti -ud. Materia4 5..... - 196.......

Material - G - 1577 pieces...........' Beginning, ATT-2X 450 pcs., ATT-2X End, ATT-5X Material - A - 2457 pieces ~.. /il 1! i}i i i l'' 1!Ji!............. Beginning 650 pcs. 2000.pcs. End ATT-2X ~ ATT-2X ATT-lOX ATT-lOX.-A ~ Maera - 122 - 2451...... pieces.... Beginning 650 pcs, ATT02X Ed, ATTnd ATT-lX AT2 T-0 T-0.......ig.26..onclded............................... 4

Material - T1 - 1207 pieces Start of ciri lling End. of -:, 1 1. ^ -,:! i: i: I. of.'. - drilling:iL Start of: iiTl:V: turning:........':'. Beginning, ATT-5X 350 pcs., ATT-5X End, ATT-5X Material - T2 - 1793 pieces ~ ~ ~ ~;-.i i......- - 1................ j. - -, - IV........ i - - ---------—... *"~~;i ^~1 —i "~ ~j -} U~..;.~....;-.._.'i.i ~: i i:!. Beginning, ATT-20X 650 pcs., ATT-20X 1500 pcs., ATT-20X End, ATT-20X Material - T3 - 1033 pieces y^ ^ ^^ _ y 2- 0.;.l 42 2.:;. 3......................... ___-...i..:~l l ll^^ ~-~-tJl.^..{.....^.............. Beginning, ATT-20X 650 pcs., ATT-20X End, ATT-20X Material - T4 - 2080 pieces' ~i - "I, ~ i < ^ 2. T;1 ^ ^ ~ i- 2 < 2 4 It 2 Beginning 600 pcs. 850 pcs. End ATT-5X ATT-5X ATT-MX ATT-5X Fig. 27. Turning and drilling tbraces of feeding and -thrust forces. ii!' —

Material -Ti - 1194 pieces 4 4~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ JIA-~~~~~~~~~ 4 Beginning, ATT-5X 750 pcs., ATT-5X End, ATT5X Material - T6 - 2002 pieces 7T7 il.~l.~.llll:liS^IS!'l-l iiil~~~~~~~~~~~~~~~~~~~~~~~~~~~i..^.:uii i~~~~~~~~~~p.1iii....... L^J I~~ ~ I < Beginning, ATT-5X 500 pcs., ATT-5X 850 pcs., ATT-5X End, ATT-5X Material - 221 emulsion - 1218 pieces.......... jl:...............~.j^p.. M ~~i'~-~:..!........i...-^...i..... i...s...;..u..i.-:i~~~~~~~~~~~l..^.:.:^ liJ": ^.i..^;: _~:: >:;~..~n ~~~~~~~~i ^ ~......~...~.;. E~ Beginning, ATT-2X End, ATT-2X Material - 221 oil - 1964 pieces Beginning, ATT 2X ^ ^nd A1'T-^' Fig. 27. Continued. 46

Material - G 1577 pieces Beginning, ATT-5X 400 pcs.,9 ATT-10X End, ATT-OX ~ ^-............... Beginning, ATT-2X 1050 pcs., ATT-2X End, ATT-2X Material - 122 2451 pieces i i. i 1-'- I:-''-r Fig..... C oncude.. ~i..: t............4 BATT-5X 40 pcs., ATT-2X End, ATT-2X f: tt:.,.....,'

MATERIA L - A IL 0 0\ BEGINNING OFR!UN ~/ 1200 PIECES -~2450 PIECES TARE HORSEPOWER EACH CURVE TRACED FROM RIGHT TO LEF MATERIAL - r END OF DRILL ING WiirOFF AND / -COMBINED CUT-START OF DRILLING ^ ^~'~UOFF I AND PARTIAL CUTOFF AND FORM A_ FORM F _ —= — 0^I TURNING BEGINNING OF RUN 750 PIECES 1200 PIECES TARE HORSEPOWER Fig. 28. Typical wattmeter-power curves showing power consumed for several machining operations. The curves show two dirilling-behavior patterns exhibited by the materials used in the test program. All but one of the materials gave beginning patterns similar to those shown on the left above, but only materials A, 122, and T6 maintained the pattern for the entire run. All other materials showed a change in drilling-power characteristics similar to the change represented above for material Ti. Material 221, with oil, was the only material to show a beginning pattern similar to the center pattern under T1 above.

UNIVERSITY OF MICHIGAN 3 9015 02841 2255