Effect of Roller Working on Fatigue Strength of Structural Metals

摘要

Three kinds of materials, pure aluminum (Al1050), carbon steel (S25C) and eutectoid steel (NHH) with V-notch are used in this study to compare the effect of roller working on the fatigue properties among the test materials. As the result, all of the fatigue strengths are improved after roller working and the optimum deformation values exist for every test materials. Fiberized microstructure at the notch bottom, work hardening and compressive residual stress caused by roller working are considered as the main reasons for the fatigue strength improvement. The highest fatigue strength improvement of All 050, S25C and NHH was 30%, 118% and 155%, respectively. The optimum fatigue improvement of NHH is the highest and it is much higher than that of All 050, and the optimum deformation value of Al 1050 is much lower than that of the other materials. Moreover, the roller working effect is much remarkable for the materials with better hardenability.