# # Fitted Curve; Manual fit near Nf=1 and fatigue limit. # SAE4140 Forged the Quenched from 1550F into 150F Oil, Temp 750F # Source: ElecFurnace, ConCast, Normalized 1650, Forged 2150 82% REDUC. # 100% Martensite, Inclus.: TypeA 0.5T OH, TypeB 0T OH, TypeC 0T 0H # TypeD(glob.) 1.0T 1.0H, Test: UoToledo. # saedigcurve_v2.2.f starts. #FileType= strain_life #DataType= fitted #Name= SAE4140 #Name= AisiIt_80 #Stress_units= MPa #Strain_units= strain #Sy= 1290.7 #Su= 1380.4 #E= 206400 #monotonic_K= 1628.5 #monotonic_n= 0.038 #LowerYield= 1282.2 #UpperYield= 1287.9 #FractureStrain= 26.9 #FractureStress= 1385. #%RA= 23.6 #MaterialForm= bar #FailureDef= 50% load drop #BHN= 394 #Hardness, Rockwell C= 42.5 #Basic Oxygen= False #Electric Furnace= True #Vacuum Degas= False #Ladle Refined= False #Ingot Cast= False #Continuous Cast= True #Martensite, %= 100 #Carbon, %= 0.41 #Manganese, %= 0.94 #Phosphorus, %= 0.01 #Sulfur, %= 0.012 #Silicon, %= 0.28 #Copper, %= 0.17 #Nickel, %= 0.15 #Chromium, %= 1.01 #Molybdenum, %= 0.22 #Aluminum, %= 0.028 #Tin, %= 0.010 #Nitrogen, ppm= 94 # SAE4140 AisiIt_80 BHN= 394 Fn= 0 # Monotonic Props. Cyclic Props. #ELAS. MOD.= 29936. KSI, 206. GPA K' = 280.3 KSI, 1933.MPA #YIELD,0.2%= 187. KSI, 1291. MPA N' = 0.1182 #ULT. STRG.= 200. KSI, 1380. MPA F. STRG COEF= 255.3 KSI, 1760.MPA #K = 0.0 KSI, 0. MPA F.STRG EXP, b=-0.0769 #N = 0.0000 FAT DUCT COEF= 0.4531 #RED. IN AREA = 23.6 F.DUCT EXP, c=-0.6511 #T. FRAC. STG.= 200.9 KSI, 1385. MPA Exp Cyc Yld = 134. Ksi, 927.MPA #T. FRAC. STR.= ***** Fit Cyc Yld = 134. Ksi, 927.MPA #No. fatigue data points= 17 # # NOTE!! The Following Points are <b>FITTED DATA:</b>#NOTE!! Fitted Stress computed using Experm. K' and n' # NOTE!! Manual fit near Nf=1 and fatigue limit #Stress_Units= MPa # Total Strain 2Nf Stress Mean Plastic Strain Initial # Amp Amp Stress Amp Elastic Mod. .269 1 1385. 0. .262 206400. #Fitted_point manually 0.02006 200 1158.9 0. 0.01445 206400. #Fitted_point 0.01321 500 1083.5 0. 0.00796 206400. #Fitted_point 0.01006 1000 1029.7 0. 0.00507 206400. #Fitted_point 0.00796 2000 978.4 0. 0.00322 206400. #Fitted_point 0.00620 5000 914.3 0. 0.00177 206400. #Fitted_point 0.00532 10000 868.2 0. 0.00112 206400. #Fitted_point 0.0049 12850 840 27.0 0.00087 210000 #Fitted_point manually 0.0033 116410 672 0.0 0.00000 0000 #Fitted_point manually .0028 2808070 569 0.0 0.00000 0000 #Fitted_point manually 0.0028 10000000 569 0.0 0.00000 0000 #Fitted_point manually #