A STUDY OF SURFACE FINISH EFFECT FACTOR IN ASME B & PV CODE SECTION III
暂无分享,去创建一个
ABSTRACT Reversed strain cycling fatigue tests were carried out on smooth solid cylindrical specimens, which had their test sections finished by three kinds of surface roughness: buff polished (0.3 micron meter in average roughness), 6S finished (5.3 micron meter in average roughness) and 25S finished (25.3 micron meter in average roughness). The experimental fatigue strength ratios were calculated for each combination of surface roughnesses in the fatigue life range up to 2x105 cycles, and the validity of the expression for Ksf, a fatigue strength modification factor for the effect of surface finish, which is defined in ASME Boiler and Pressure Vessel Code, Section III, Division 1, Appendix II, was discussed, deriving a conclusion that the calculation formula for Ksf in the Code gives approximately 15% nonconservative estimation in the worst case.