# # Fitted Curve ! # SAE8620 Thru Carburized Rc= 61 # Material cyclically hardens to elastic condition. # ElecFurnace, LadleRefined, ConCast(152x152) HotRolled to 29.7mm bar # Specimens machined, carburized, reaustenitized and isothermally transformed # to achieve 100% martensite and 0%bainite. # Inclusions: TypeA=1.2T 0.H, TypeB=0.5T 0.3H, TypeC=0.2T, TypeD=1.5T 0.5H # Test: UoWaterloo, A.Rteil and T.Topper, June 2007 # saedigcurve_v2.2.f starts. #FileType= strain_life #DataType= fitted #Name= SAE8620 #Name= AisiIt_87 #Stress_units= MPa #Strain_units= strain #Sy= 1252.0 #Su= 1485.0 #E= 198000 #monotonic_K= 5575.0 #monotonic_n= 0.240 #FractureStrain= 0.0125 #FractureStress= 1330 #%RA= 0 (not measurable) #MaterialForm= bar #FailureDef= 50% load drop #Hardness, Rockwell C= 61 #BHN= 670 #Basic Oxygen= False #Electric Furnace= True #Vacuum Degas= False #Ladle Refined= True #Ingot Cast= False #Continuous Cast= True #Martensite, %= 100 #Carbon, %= 0.21 #Manganese, %= 0.83 #Phosphorus, %= 0.009 #Sulfur, %= 0.032 #Silicon, %= 0.25 #Copper, %= 0.15 #Nickel, %= 0.46 #Chromium, %= 0.5 #Molybdenum, %= 0.2 #Vanadium, %= 0.00 #Columbium/Niobium, %= 0.00 #Aluminum, %= 0.024 #Lead, %= 0.000 #Titanium, %= 0.002 #Calcium, %= 0.00 #Cobalt, %= 0.010 #Zirconium, %= 0.000 #Boron, %= 0.0003 #Tin, %= 0.010 #Oxygen, ppm= 9 #Nitrogen, ppm= 63 # SAE8620 AisiIt_87 BHN= 670 Fn= 0 # Monotonic Props. Cyclic Props. #ELAS. MOD.= 28717. KSI, 198. GPA K' = 0.0 KSI, 0.MPA #YIELD,0.2%= 182. KSI, 1252. MPA N' = 0.0000 #ULT. STRG.= 215. KSI, 1485. MPA F. STRG COEF= 504.5 KSI, 3478.MPA #K = 0.0 KSI, 0. MPA F.STRG EXP, b=-0.1175 #N = 0.0000 FAT DUCT COEF= 0.0000 #RED. IN AREA = 0.0 F.DUCT EXP, c= 0.0000 #T. FRAC. STG.= 192.9 KSI, 1330. MPA Exp Cyc Yld = 0. Ksi, 0.MPA #T. FRAC. STR.= 0.013 Fit Cyc Yld = 0. Ksi, 0.MPA #No. fatigue data points= 21 # # NOTE!! The Following Points are <b>FITTED DATA:</b>#NOTE!! Fitted Stress computed using Experm. K' and n' # NOTE!! Due to zero cyclic plasticity, material fit is on elastic strain vs life line. #Stress_Units= MPa # Total Strain 2Nf Stress Mean Plastic Strain Initial # Amp Amp Stress Amp Elastic Mod. 0.01757 1 3478 0. 0 198000. #Fitted_point .0080 1368 1521 0. 0 198000. #Fitted_point manually 0.00287 5000000 568 0. 0 198000. #Fitted_point .00276 10000000 540 0. 0 198000. #Fitted_point manually #