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Home/About SAE Grade Index Project Index Carburizing Steel Index Iteration No. Index
 


Project 4:
The fatigue data in this test group compares the
fatigue properties of SAE 1141 re-sulfurized steel
manufacturing. Properties in the normalized and
quenched and tempered condition are included.
(an 1151V As rolled has been added for comparison)

SAE
Grade		 Process Iter Fat.Str.
@ N=106
(MPa)		 YS
(MPa)		 UTS
(MPa)		 %RA %ELong. BHN  
1141AL Normalized, 1650 11 286.0 457.4 770.6 57.0 40.0 223
1141AL Quenched + Tempered 12 432.0 814.2 924.8 59.0 32.0 277
1141Nb Normalized 1650 13 276.6 417.8 695.2 53.0 35.0 199
1141Nb Quenched and Tempered 14 341.8 602.1 801.8 54.0 32.0 241
1141V Normalized 1650 15 287.0 449.9 725.2 49.0 32.0 217
1141V Quenched and Tempered 16 332.2 609.7 796.8 58.0 34.0 252
1141V Normalized 1750 17 295.8 493.5 789.4 47.0 30.0 229
1151V HotFormed, Control Cooled- Tested As-HotRolled 27 266.9 452.3 760.8 50.6 26.3 205

Results: All Normalized Normal.+It027(hotRolled) Q+T + It027(HotRolled) All StrainLife All NeuberStress


Project 7:
Fatigue data for several spring steels at various hardness levels.
SAE
Grade		 Process Iter Fat.Str.
@ N=106
(MPa)		 YS
(MPa)		 UTS
(MPa)		 %RA %ELong. BHN  
51B60 Quenched and Tempered 33 771.0 1830.0 1970.0 21.6 36.2 450
9254V Quenched and Tempered 34 710.2 1870.0 2050.0 35.1 16.2 536
9254 AL FG Quenched and Tempered 35 844.9 2270.0 2450. 4.0 3.9 627
5160H Quenched and Tempered 84 736.9 1604.2 1761.2 30.2 13.9 477
6150 Quenched and Tempered 85 406.6 1878.2 2342.8 0.0 0.0 653
9254 Quenched and Tempered 86 664.6 1841.0 2020.0 51.0 8.0 514

Results: Strain vs 2Nf Cyclic Stress-strain Neuber


Project 8:
Fatigue properties for 4100 series low alloy quenched and tempered steels.
Iteration Nos. 64-69 were designed to evaluate data scatter.
Micros. and Hardness Report (iters.64-69)
SAE
Grade		 Process Iter Fat.Str.
@ N=106
(MPa)		 YS
(MPa)		 UTS
(MPa)		 %RA %ELong. BHN  
4130 AL Quenched and Tempered (.022 S) 29 527.6 1284.5 1482.8 44.3 28.0 442
4140 Quenched and Tempered (.021 S) 30 437.4 928.9 1042.9 61.3 30.8 325
4140 Quenched and Tempered (.021 S) 64 602.5 1297.0 1390.0 48.3 18.5 380
4140 Quenched and Tempered (.021 S) 65 607.5 1305.6 1400.5 48.2 22.0 375
4140 Quenched and Tempered (.021 S) 66 626.3 1330.0 1537.0 42.1 19.7 388
4140 Quenched and Tempered (.009 S) 67 697.3 1314.0 1445.8 52.1 27.3 380
4140 Quenched and Tempered (.009 S) 68 679.0 1255.1 1355.1 38.8 24.2 352
4140 Quenched and Tempered (.009 S) 69 730.4 1341.0 1474.2 52.5 28.2 375
4140 Induction Thru Hardened (.009 S) 93 552.4 1363.0 1514.0 48.0 19.0 352

Results(sort by BHN): Strain vs 2Nf Cyclic Stress-strain Neuber
Results(sort by Sulfur%): Strain vs 2Nf Neuber
Iters.64-69 only (sort by BHN): Strain vs 2Nf Cyclic Stress-strain Neuber


Project 10:
Compare the fatigue properties for SAE 4620 produced by
continuous casting of blooms versus
continuous casting of billets.
SAE
Grade		 Process Iter Fat.Str.
@ N=106
(MPa)		 YS
(MPa)		 UTS
(MPa)		 %RA %ELong. BHN  
4620 Quench+Temp Simul. Carburized Core
Bloom Cast		 47 368.5 687.5 997.8 58.2 34.0 277
4620 Thru Carburized Simulated Case
Bloom Cast		 48 763.9 1316.6 2226.9 4.0 1.25 614
4620 Quench+Temper Simulated Carburized Core
Billet Cast		 53 453.5 891.5 963.7 61.9 43.0 285
4620 Thru Carburized Simulated Case
Billet Cast		 54 737.6 1169.1 1775.6 1.4 7.7 682

Results: Core Strain-Life Case Strain-Life Cyclic Stress-strain Core Neuber Case Neuber


Project 9:
Compare the fatigue properties of the high hardness case
and low hardness core for several carburizing steels.
The high hardness cases were simulated by through carburizing,
and the low hardeness cores were simulated by a carburizing
thermal cycle in a neutral atmosphere.

Part A: Thru Carburized Simulated Case

SAE
Grade		 Process S
wt%		 Iter Fat.Str.
@ N=106
(MPa)		 YS
(MPa)		 UTS
(MPa)		 %RA %ELong. BHN  
8620 Thru Carburized Simul. Case 0.027 38 458 920 1202 1.0 1.0 583
8620 Thru Carburized Simulated Case Repeat of Iter. 38 0.027 71 796 1125 1869 0.7 1.7 653
8695 Lab. Melted Simulated Carburized Case w/o IGO 0.028 40 401 780 1496 1.3 1.3 682
8695 Lab Melted Simulated Carburized Case with IGO 0.028 41 509 847 979 1.0 1.0 653
4620 Thru Carburized Simulated Case 0.016 48 764 1317 2227 4.0 1.25 614
4320 Thru Carburized Simulated Case 0.020 50 819 1250 2.2 2.1 600
1117 Thru Carburized Simulated Case 0.215 52 361 880 0.5 0.5 625
4620 Thru Carburized Simulated Case 0.030 54 737.6 1169 1776 1.4 7.7 682
5120 Thru Carburized Simulated Case 0.025 56 664.0 1161 1403 2.7 1.2 682
9310 Thru Carburized Simulated Case 0.018 58 650 1024 1636 2.9 1.9 682
1070 Induction Hardened Simulated Case 0.024 37 533 1950 2069 2.3 3.3 682
1552 Thru Induction Hardened Simulated Case 0.012 92 257 933 0.0 0.5 627

Results: StrAmpl. vs 2Nf Cyclic Stress-strain Neuber
Fatigue Strength vs HRc: Literature Lit.+Proj.9A Lit.+Proj.9A with Iter.No.


Part B Simulated Carburized Core
The low hardeness cores were simulated by a carburizing
thermal cycle in a neutral atmosphere.

SAE
Grade		 Process S
wt.%		 Iter Fat.Str.
@ N=106
(MPa)		 YS
(MPa)		 UTS
(MPa)		 %RA %ELong. BHN  
8620 Quenched and Tempered Simulated Carburized Core 0.027 39 508 1420 1683 36.2 47.7 420
15B35 Quenched and Tempered Simulated Carburized Core 0.017 45 468 866 940 64.5 37.3 285
4620 Quenched and Tempered Simulated Carburized Core 0.016 47 369 688 998 58.2 34.0 277
4320 Quenched and Tempered Simulated Carburized Core 0.020 49 547 920 994 63.0 43.0 201
1117 Quenched and Tempered Simulated Carburized Core 0.215 51 387 655 777 55.0 37.0 193
4620 Quenched and Tempered Simulated Carburized Core 0.030 53 451 892 964 61.9 43.0 285
5120 Quenched and Tempered Simulated Carburized Core 0.025 55 472 780 1008 58.0 46.0 252
9310 Quenched and Tempered Simulated Carburized Core 0.015 57 479 804 902 70.8 31.0 259
8822 Quenched and Tempered Simulated Carburized Core 0.013 59 442 918 1131 56.0 40.0 252
1070 Induction Hardened Simulated Core 0.024 36 339 520 659 36.2 25.1 280
1552 As Rolled Simulated Induction Hardened Core 0.012 94 387 420 964 45.0 15.0 248

Results: StrAmpl. vs 2Nf Cyclic Stress-strain Neuber

Project 9C: Compare 9A(case) vs 9B(core)
Results: StrAmpl. vs 2Nf Cyclic Stress-strain Neuber


Project 12:
Torsion fatigue data for a high performance spring steel
and carbon steel used in shafts.

SAE
Grade		 Process Iter Fat.Str.
@ N=106
(MPa)		 YS
(MPa)		 UTS
(MPa)		 %RA %ELong. BHN  
9254 AL Quenched and Tempered Torsion Tested
(for Axial Props.see Iter.35 )		 44_pdf
1050M Quenched and Tempered Torsion Tested
(for Axial Props.see similar hardness tests on 1050M page )		 61_pdf


Project 13:
Compare the fatigue properties of the high hardness case
for SAE 8620 when varying percentages of Bainite are
present in the Martensitic microstructure.

SAE
Grade		 Process Iter Fat.Str.
@ N=106
(MPa)		 YS
(MPa)		 UTS
(MPa)		 %RA %ELong. BHN  
8620 Through Carburized Simulated Case Quenched and Tempered 100% Martensite 0% Bainite 87 543.9 1252.0 1485.0 0.0 1.2 673
8620 Through Carburized Simulated Case Isothermally Transformed to 75% Martensite 25% Bainite 88 758.4 1206.0 1390.0 0.0 1.0 745
8620 Through Carburized Simulated Case Isothermally Transformed to 50% Martensite 50% Bainite 89 565.6 1114.0 1497.0 0.0 1.3 682
8620 Through Carburized Simulated Case Isothermally Transformed to 25% Martensite 75% Bainite 90 570.0 1314.0 1883.0 0.0 2.2 614
8620 Through Carburized Simulated Case Isothermally Transformed to 100% Bainite 95 614.6 1566.0 1785.0 39.0 15.0 470

Note: Except for the 100% Bainite iteration all of the above had a case+core structure.
and exhibited sub-surface failures at long fatigue lives.
Results: Web Page with Results


Project 14:
Determine if the fatigue properties of PS19 are sufficient to
permit substitution for 86B20 in carburized applications.
Test data were developed for carburized cases and cores under
conditions of both atmosphere and vacuum carburizing.

SAE
Grade		 Process Iter Fat.Str.
@ N=106
(MPa)		 YS
(MPa)		 UTS
(MPa)		 %RA %ELong. BHN  
Carburize in Atmosphere
41B17M (PS19) Quenched and Tempered Simulated Carburized Core (Atmosphere) 72 465.5 826.9 872.3 68.0 38.8 277
41B17M (PS19) Thru Carburized Simulated Carburized Case (Atmosphere) 73 235.4 1275.0 1275.0 1.0 1.0 665
86B20 Quenched and Tempered Simulated Carburized Core (Atmosphere) 74 498.6 989.0 1034.1 63.7 29.7 336
86B20 Thru Carburized Simulated Carburized Case (Atmosphere) 75 535.6 1114.9 1309.4 0.3 1.5 710
Vacuum Carburized
41B17M (PS19) Quenched and Tempered Simulated Carburized Core (Vacuum) 78 480.5 863.1 904.0 64.7 42.0 285
41B17M (PS19) Thru Carburized Simulated Carburized Case (Vacuum) 79 475.2 1727.8 1876.8 5.5 2.0 653
86B20 Quenched and Tempered Simulated Carburized Core (Vacuum) 82 494.8 1198.0 1502.0 59.7 59.5 401
86B20 Thru Carburized Simulated Carburized Case (Vacuum) 83 444.4 1349.6 1349.6 0.7 0.8 670

Results:   PS19 Atmos. vs Vacuum: Core Str-Life Case Str-Life
PS19 and 86B20 Atmos. vs Vacuum, Core: Str-Life CyclicSS NeuberStress
PS19 and 86B20 Atmos. vs Vacuum, Case: Str-Life CyclicSS NeuberStress


Project 15:
Fatigue properties of SAE 4140 steel containing various
amounts of sulfur. Test data was developed for both
longitudinal(Iter.96 and 97) and transverse orientations.
Also contains Periodic Overload Tests (POL) from Project 17.

SAE
Grade		 S
 wt% 		 Process Iter Fat.Str.
@ N=106
(MPa)		 YS
(MPa)		 UTS
(MPa)		 %RA %ELong. BHN
4140 .077 High Sulfur, Billet Forged to Test Block,
Normalized, Quench + Temper, Transv. Tested		 77 309 1602 1680 1.5 3.0 477
4140 .077 High Sulfur, Billet Forged to Test Block,
Normalized, Quench+Temper, Transv. Tested		 81 429 1263 1299 1.3 1.5 395
4140 .077 High Sulfur, Billet Forged to Test Block,
Normalized, Quench+Temper, Transv. Tested, POL		 118 1263 1299 1.3 1.5 395
4140 .077 High Sulfur, Mill Induction Hardened Longitudinal 97 575 1167 1240 47.2 24.7 417
4140 .021 Quenched and Tempered 30 437 929 1043 61.3 30.8 325
4140 .021 Quenched and Tempered 64 603 1297 1390 48.3 18.5 380
4140 .021 Quenched and Tempered 65 608 1306 1401 48.2 22.0 375
4140 .021 Quenched and Tempered 66 626 1330 1537 42.1 19.7 388
4140 .015 Low Sulfur, Mill Induction Hardened, Longitudinal 96 602 1158 1248 47.5 24.5 409
4140 .012 Low Sulfur, Billet Forged to Test Block,
Normalized, Quench+Temper, Transv. Tested		 76 588 1669 1924 15.7 8.5 477
4140 .012 Low Sulfur, Billet Forged to Test Block,
Normalized, Quench+Temper, Transv. Tested		 80 555 1291 1380 23.6 23.0 394
4140 .012 Low Sulfur Billet Forged to Test Block,
Normalized, Quench+Temper, Transv. Tested, POL 		117 1291 1380 23.6 23.0 394
4140 .009 Quenched and Tempered 67 697 1314 1446 52.1 27.3 380
4140 .009 Quenched and Tempered 68 679 1255 1355 38.8 24.2 352
4140 .009 Quenched and Tempered 69 730 1341 1474 52.5 28.2 375
4140 .009 Induction Thru Hardened 93 552 1363 1514 48.0 19.0 352
4140 .004 Ultra-Low Sulfur, Billet Forged to Test Block,
Normalized, Quench+Temper, Transv. Tested		 98 638 1622 1818 42.6 18.7 477
4140 .004 Ultra-Low Sulfur, Billet Forged to Test Block,
Normalized, Quench+Temper, Transv. Tested		 99 574 1261 1333 44.0 30.8 375
4140 .004 Ultra-Low Sulfur, Billet Forged to Test Block,
Normalized, Quench+Temper, Transv. Tested, POL		 116 1261 1333 44.0 30.8 375
Results Project 15:
    See also : GDIS Presentation by N.Cyril, A.Fatemi, B.Cryderman, 2008, also in SAE paper :SAE Paper No. 2008-01-0434
Project 15 Comparison graphs:
BHN= 477 only compare: Strain vs 2Nf Cyclic Stress-strain Neuber
BHN= 477 +iter81(Bhn=395) : Strain vs 2Nf Cyclic Stress-strain Neuber
BHN= 350 to 420 (w/o iter.81): Strain vs 2Nf Cyclic Stress-strain Neuber
Results Project.17:
Compare %S Const.Ampl. vs Periodic Overload tests Iters.: 81(CA)118(POL) Strain vs 2Nf
Compare %S and Periodic Overload tests Iters.: 118,117,116 Strain vs 2Nf Neuber


Project 16:
Fatigue properties of a carburizing steel (SAE8822) at the extremes of
its composition range and hardenability. Data for both cases and cores
under conditions of both Atmosphere and Vacuum carburizing.
In addition the effects of periodic overloads(POL) during
constant amplitude(CA) fatigue testing are evaluated.

Low Side Chem.:     wt% .21C   .81Mn   .02P   .026S   .26Si   .18Cu   .46Ni   .50Cr   .25Mo   .005V   .002Nb   .031Al   .01Sn   15ppm_O

SAE
Grade		 Process Iter Fat.Str.
@ N=106
(MPa)		 YS
(MPa)		 UTS
(MPa)		 %RA %ELong. BHN  
8822 Low Side Chem. Quench+Temper Simulated Carburized Core (Atmosphere) CA 100 511. 884 946 67.2 36.8 297
8822 Low Side Chem. Quench+Temper Simulated Carburized Core (Atmosphere) POL 104 884 946 67.2 36.8 297
8822 Low Side Chem. Thru Carburized Simulated Carburized Case (Atmosphere) CA 101 524 1082 1082 0 0.57 615
8822 Low Side Chem. Thru Carburized Simulated Carburized Case (Atmosphere) POL 105 1082 1082 0 0.57 615
8822 Low Side Chem. Quench+Temper Simulated Carburized Core (Vacuum) CA 102 549 990 1335 46.9 23.8 301
8822 Low Side Chem. Quench+Temper Simulated Carburized Core (Vacuum). POL 106 990 1335 46.9 23.8 301

High Side Chem.:     wt% .22C   .86Mn   .013P   .025S   .17Si   .24Cu   .43Ni   .54Cr   .39Mo   .004V               .028Al   .01Sn

SAE
Grade		 Process Iter Fat.Str.
@ N=106
(MPa)		 YS
(MPa)		 UTS
(MPa)		 %RA %ELong. BHN  
8822 High Side Chem. Quench+Temper Simulated Carburized Core (Atmosphere) CA 108 609 1135 1215 59.4 55.0 363
8822 High Side Chem. Quench+Temper Simulated Carburized Core (Atmosphere). POL 112 1135 1215 59.4 55.0 363
8822 High Side Chem. Thru Carburized Simulated Carburized Case (Atmosphere) CA 109 1480 0.9 555
8822 High Side Chem. Thru Carburized Simulated Carburized Case (Atmosphere). POL 113 1480 0.9 555
8822 High Side Chem. Quench+Temper Simulated Carburized Core (Vacuum) CA 110 535 1528 1723 50.0 13.0 375
8822 High Side Chem. Quench+Temper Simulated Carburized Core (Vacuum). POL 114 1528 1723 50.0 13.0 375
Results Project 16: Compare Plots
LowSide vs HighSide Case (Atmos.) CA + POL Strain vs 2Nf Cyclic Stress-strain Neuber
LowSide + HighSide Core (Atmos) CA + POL Strain vs 2Nf Cyclic Stress-strain Neuber
LowSide + HighSide Core (Atmos. + Vac.) CA Strain vs 2Nf Cyclic Stress-strain Neuber
LowSide + HighSide Core (Atmos. + Vac.) POL Strain vs 2Nf Cyclic Stress-strain Neuber
Other Observations:
    1. Carb. Case using Vacuum were not tested.
    2. Note that U.Toledo POL tests applied 1000 cycles at Overload
    amplitudes(about 10% of fatigue life at that level)
    before begining the Periodic Overload tests(e.g. 101+105)
    The U.Waterloo POL tests did not have any pre-cycles, but only
    consisted of periodic single overloads(e.g.Iter.108+112)
    Judgement on which is more appropriate is left to the reader.

Project 18:
Fatigue properties of carburized cores of several
carburizing steel grades which have varying microstructures
and hardness levels. Microstructure and hardness are controlled
during the carburizing thermal cycle by varying section size.
Comparisons are made for both Constant Amplitude(CA) and
Periodic Overload(POL) tests.
Note that after hot rolling heat treatment of the bar was the same for all iterations:
Bars provided at different diameters were heat treated using the same quench to get
different cooling rates and thus different microstructures and hardness levels.
Specimens were machined after heat treatment. The purpose was to evaluate what
really happens with core microstructure as carburized part size changes.
(Work in other projects looked at hardness changes achieved by quenching
the small specimens and tempering at different temperatures to look at the effect of hardness.)
SAE
Grade		 Process Bar
Diam.
(mm)		 CA
Iter		 POL
Iter		 CA
Fat.Str.
@ N=106
(MPa)		 YS
(MPa)		 UTS
(MPa)		 %RA %ELong. BHN  
8620 Quench+Temper Simul. Carburized Core. Section Controlled Cooled HRc= 32 24.1 119 143 380 694 991 54.0 32.4 326
8620 Quench+Temper Simul. Carburized Core. Section Controlled Cooled HRc= 38 19.1 120 144 430 796 1145 50.8 35.5 352
8620 Quench+Temper Simul. Carburized Core, Section Controlled Cooled HRc= 41 15.2 121 145 528 990 1310 52.0 26.9 382
4320 Quench+Temper Simul. Carburized Core. Section Controlled Cooled HRc= 29 30.5 122 146 392 621 905 59.2 11.0 277
4320 Quench+Temper Simul. Carburized Core. Section Controlled Cooled HRc= 30.4 22.9 123 147 466 745 1010 57.0 11.3 285
4320 Quench+Temper Simul. Carburized Core. Section Controlled Cooled HRc= 38.6 15.2 124 148 677 867 1238 55.2 11.0 363
9310 Quench+Temper Simul. Carburized Core. Section Controlled Cooled HRc= 28.6 66 125 149 450 666 883 61.4 13.2 277
9310 Quench+Temper Simul. Carburized Core. Section Controlled Cooled HRc= 35.2 25.4 126 150 531 850 1085 57.5 9.9 331
9310 Quench+Temper Simul. Carburized Core. Section Controlled Cooled HRc= 37.9 15.2 127 151 533 990 1201 56.5 8.8 352
20MnCr5 Quench+Temper Simul. Carburized Core. Section Controlled Cooled HRc= 23 60.9 128 152 399 695 960 50.7 13.8 265
20MnCr5 Quench+Temper Simul. Carburized Core. Section Controlled Cooled HRc= 32 27.9 129 153 489 852 1053 56.5 11.3 302
20MnCr5 Quench+Temper Simul. Carburized Core. Section Controlled Cooled HRc= 42 15.2 130 154 607 1071 1337 52.0 10.4 388

8620 Comparisons: Strain vs 2Nf Neuber
4320 Comparisons: Strain vs 2Nf Neuber
9310 Comparisons: Strain vs 2Nf Neuber
20MnCr5 Comparisons: Strain vs 2Nf Neuber
All Results: Strain vs 2Nf Cyclic Stress-strain Neuber
Other Observations:
1. Hardness vs Section Size(graph)
2. SAE4320 fatigue life appears to be more sensitive to hardness than the other materials.
3. Note that the POL test of 8620 applied 1000 pre-cycles at the overload level prior to the periodic overload test portion. This significantly affected fatigue life. Whether or not this is appropriate is left to engineering judgement.


Project 19:
Compare the fatigue properties of 1538MV microalloyed steel in both the as-hot rolled and
forged conditions. The effects of periodic overloads(POL) during constant amplitude(CA)
fatigue testing were also studied.
SAE
Grade		 Process CA
Iter		 POL
Iter		 CA
Fat.Str.
@ N=106
(MPa)		 YS
(MPa)		 UTS
(MPa)		 %RA %ELong. BHN  
1538MV As-Hot Rolled Bar HRc= 30 131 132 439 650 973 28.3 24.9 285
1538MV Forged Crankshafts. Specimens From 5 Crankshafts from 5 Heats of Steel. HRc= 29 133 134 382 628 943 36.4 26.7 277
Results: Strain vs 2Nf(CA) Strain vs 2Nf(POL) Cyclic Stress-strain Neuber

Other Observations: 1. The materials appear to have similar fatigue behavior.


Project 20:

Evaluate the fatigue properties of the Case and Core of 20MoCr4 steel for
both Atmosphere and Vacuum carburizing. The effects of periodic overloads(POL)
during constant amplitude(CA) fatigue testing were also examined.
SAE
Grade		 Process CA
Iter		 POL
Iter		 CA
Fat.Str.
@ N=106
(MPa)		 YS
(MPa)		 UTS
(MPa)		 %RA %ELong. BHN  
20MoCr4 (Atmosphere) Quench+Temper Simul. Carburized Core HRc=35 135 136 478 837 987 51.0 26.0 327
20MoCr4 (Atmosphere)Thru Carburized Simul. Case HRc= 59 137 138 461 1265 1394 0.0 0.0 627
20MoCr4 (Vacuum) Quench+Temper Simul. Carburized Core HRc=35 139 140 434 870 1288 51.6 34.1 326
20MoCr4 (Vacuum) Thru Carburized Simul. Case HRc=60 141 142 465 965 0.0 3.2 653

Case Results: Tensile tests CA Strain vs 2Nf POL Strain vs 2Nf CA Neuber
Core Results: CA Strain vs 2Nf POL Strain vs 2Nf CA Neuber



Project 21-A:
Compare Axial and Bending fatigue properties of 8615 Carburizing steel.
Carburization was done in Atmosphere with one set of specimens having a
Shallow (5% of gage) Case Depth, and another set having a
Deep (10% of gage) Case Depth. Includes both Constant Amplitude(CA)
and Periodic Overload(POL) testing.
All samples in this series from same heat of steel. (Sulfur= 0.035 wt%)
SAE
Grade		 Process CA
Iter		 POL
Iter		 CA
Fat.Str.
@ N=106
(MPa)		 YS
(MPa)		 UTS
(MPa)		 %RA %ELong. BHN  
8615 Quench+Temper Simul. Carburized Core (Atmosphere) Axial, HRc=20 155 452 753 1011 61.5 36.5 225
8615 Quench+Temper Simul. Carburized Core (Atmosphere) 4-Point Bend, HRc=30 156 285
8615 Carburized Case/Core Composite (Atmosphere). Shallow Case Depth, Axial 157 158 636 921 1154 8.5 8.1 653
8615 Carburized Case/Core Composite (Atmosphere). Shallow Case Depth. 4-Point Bend 159 160 653
8615 Carburized Case/Core Composite (Atmosphere). Deep Case Depth, Axial 161 162 721 1017 1182 2.5 2.8 673
8615 Carburized Case/Core Composite (Atmosphere). Deep Case Depth. 4-Point Bend 163 164 673
8615 CA Axial vs Bend Results: Core Strain-2Nf (155,156) Shallow Case Strain-2Nf (157,159) Deep Case Strain-2Nf (161,163)
8615 Axial Results: CA Strain vs 2Nf (155,157,161) POL Strain vs 2Nf (158,162)
8615 4pt-Bending Results: CA Strain vs 2Nf (156,159,163) POL Strain vs 2Nf (160,164)
Project 21-B: 9310 carburizing steel 0.014%S
SAE
Grade		 SAE Process CA
Iter		 POL
Iter		 CA
Fat.Str.
@ N=106
(MPa)		 YS
(MPa)		 UTS
(MPa)		 %RA %ELong. BHN  
9310 Quench+Temper Simul.Carburized Core Axial, Wrong HeatTreat 176
9310 Substitute for It.176: Quench+Temper Sim.Carbur. Core.
Section Control Cooled HRc=37.9 		127 151 533 990 1201 56.5 8.8 352
9310 Quench+Temper Simul. Carburized Core (Atmosphere) 4 Point Bend HRc=37.4 177 348
9310 Carburized Case/Core Composite (Atmosphere) Shallow case depth, Axial, not available 178 179
9310 Carburized Case/Core Composite(Atmosphere) Shallow case depth, 4 Point Bend 180 181 653
9310 Carburized Case/Core Composite (Atmosphere) Deep case depth, Axial, not available 182 183
9310 Carburized Case/Core Composite (Atmosphere) Deep case depth, 4-Point Bend 184 185 653
9310 CA Axial vs Bend Results: Core Strain-2Nf (127,177) Shallow Case Strain-2Nf (178,180) Deep Case Strain-2Nf (182,184)
9310 Axial Results: CA Strain vs 2Nf (127,168,178,182) POL Strain vs 2Nf (151,169,179,183)
9310 4pt-Bending Results: CA Strain vs 2Nf (177,180,184) POL Strain vs 2Nf (181,185)
Project 21-C: 16MnCr5 carburizing steel (0.034%S)
SAE
Grade		 SAE Process CA
Iter		 POL
Iter		 CA
Fat.Str.
@ N=106
(MPa)		 YS
(MPa)		 UTS
(MPa)		 %RA %ELong. BHN  
16MnCr5 Quenched and Tempered Simulated Carburized Core, Axial Testing 186 556 1040 1398 32.0 26.4 415
16MnCr5 Quenched and Tempered Simulated Carburized Core. Four Point Bend Testing 187 380
16MnCr5 Carburized Case/Core Composite (Atmosphere). Shallow case depth, Axial 188 189
16MnCr5 Carburized Case/Core Composite (Atmosphere). Shallow case depth, 4-Point Bend 190 191
16MnCr5 Carburized Case/Core Composite (Atmosphere). Deep case depth, Axial, Not Available yet 192 193
16MnCr5 Carburized Case/Core Composite (Atmosphere). Deep case depth, 4-Point Bend 194 195
16MnCr5 CA Axial vs Bend Results: Core Strain-2Nf (186,187) Shallow Case Strain-2Nf (188,190) Deep Case Strain-2Nf (192,194)
16MnCr5 Axial Results: CA Strain vs 2Nf (186,188,192) POL Strain vs 2Nf (189,193)
16MnCr5 4pt-Bending Results: CA Strain vs 2Nf (187,190,194) POL Strain vs 2Nf (191,195)

Project 21R:

Compare Rotating Bending tests with other tests for several materials.
(Testing not completed)
SAE
Grade		 Process CA
Iter		 CA
Fat.Str.
@ N=106
(MPa)		 YS
(MPa)		 UTS
(MPa)		 %RA %ELong. BHN
8620 Carburized Steel Case + Core, Rotating Bending HRc=61.4 171 682
8620 Quench+Temper Simul. Carburized Core, Axial 39 508 1420 1683 36.2 47.7 420
8620 Thru Carburized(Vacuum) Simul. Case Axial HRc=62 165 239 690 757 0.2 0.5 688
8620 Thru Carburized Simul. Case Axial HRc=58.2 71 796 1125 1869 0.7 1.7 653
8695 Lab. Melted Simulated Carburized Case w/o IGO, HRc=55 40 401 780 1496 1.3 1.3 682
8615 Carburized Case/Core Composite (Atmosphere). Shallow Case Depth. 4-Pt. Bend HRc=60 159 653
8620 Carburized Case/Core Composite, Surf 57HRC, Eff Case 0.024", Core 47HRC, Axial 62 806 1357 1764 13.9 6.0 601
4320 Carburized Steel Case + Core, Rotating Bending Not Available Yet 172
20MnCr5 Carburized Case and Core, Rotating Bending HRc=62 173 682
20MnCr5 Quench+Temper Simul. Carbur. Core Section Controlled Cooled 129 489 852 1053 56.5 11.3 302
20MnCr5 Thru Carburized Case (Vacuum) HRc=60 170 220 684 0.2 0.5 653
9310 Carburized Steel Case + Core, Rotating Bending Not Available Yet 174
1538MV Controlled Cooled, Rotating Bending Not Available Yet 175

8620/15 Results: Strain vs 2Nf
20MnCr5 Results: Strain vs 2Nf
From Literature: Garwood Morrow Murakami Garwood+Morrow Gar.+Mor +Project 9
Other comparison results not available yet.
Suggestion: Check also Project 9C


Project 22:
The Effect of alloy content in carburized case material on axial fatigue properties.
Percent Ni and %Retained Austenite were of particular interest.
See Cryderman Report on microstructure and chemistry. (AISI Phase XII)
SAE
Grade		 Process %Ni %Ret.
Aust.		 CA
Iter		 POL
Iter		 CA
Fat.Str.
@ N=106
(MPa)		 YS
(MPa)		 UTS
(MPa)		 %RA %ELong. BHN  
8620 Thru Carburized Simulated Case (Vacuum) HRc=62 0.50% ? 165 166 239 690 757 0.2 0.5 688
4320 Thru Carburized Simulated Case (Vacuum) HRc=60 1.75% 20.1% 167 265 783 0.3 0.6 653
9310 Thru Carburized Simulated Case (Vacuum) HRc=59 3.12% 23.4% 168 169 341 764 1019 0.4 0.9 653
20MnCr5 Thru Carburized Simulated Case (Vacuum) HRc=60 0.16% 13.6% 170 220 684 0.2 0.5 653

CA Results: Strain vs 2Nf Cyclic Stress-strain Neuber
POL Results: Strain vs 2Nf Neuber


Project 23:
Compare the effects of carburizing at 1900F(New) versus
traditional 1700F temperatures. Two materials and
both tested with Axial and 4pt. Bending samples.
Carburized at 1700F
SAE
Grade		 Process Axial
Iter		 4Pt.Bend
Iter		 Fat.Str.
@ N=106
(MPa)		 YS
(MPa)		 UTS
(MPa)		 %RA %ELong. BHN  
16MnCr5(Mod) Simulated Carburized Core, 1700F Carb. 204 205 1050 1370 48.1 22.4
16MnCr5(Mod) Thru Carburized 1700F Simul. Case, Axial at DANA 208 209
4120(Mod) Simulated Carburized Core, 1700F Carb. 206 207
4120(Mod) Thru Carburized 1700F Simul. Case., Axial At DANA 210 211
Carburized at 1900F
SAE
Grade		 Process Axial
Iter		 4Pt.Bend
Iter		 Fat.Str.
@ N=106
(MPa)		 YS
(MPa)		 UTS
(MPa)		 %RA %ELong. BHN  
16MnCr5(Mod) Simulate Carburized Core 1900F Carb. 196 197
16MnCr5(Mod) Thru Carb.(1900F) Case, Axial At DANA 200 201
16MnCr5 Not Modified ! Case+Core Composite, 4pt-Bend
(Check for Grain Growth)		 201A
4120(Mod) Simulate Carburized Core 1900F Carb. 198 199
4120(Mod) Thru Carb.(1900F) Case, Axial at DANA 202 203
Results not available yet.
Results: Strain vs 2Nf Cyclic Stress-strain Neuber


Project 24:
Example of Gear Tooth Fatigue.
SAE
Grade		 Process Iter Fat.Str.
@ N=106
(MPa)		 Case
Depth.
mm		 Surface
HRc		 Core
HRc		 IGO depth
mm 		Ret.Aust.
%		 Surf.Resid.
Stress mpa		 Dist. to
1st Bainite
mm		  
8620 Gear Teeth Bending, Carb. Case+Core
Meritor tests. Smin/Smax: R= 0.1		 42 1.83 60.8 35.7 0.0241 25.6 330 1.35
Simulation Results: (not available yet )
Results: Compare1