Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7171438 | International Journal of Fatigue | 2018 | 26 Pages |
Abstract
High-cycle fatigue tests of compacted graphite iron (CGI) at 25â¯Â°C, 400â¯Â°C and 500â¯Â°C were performed. The corresponding fatigue damage mechanisms were investigated by the observations on fractographies and longitudinal section morphologies of typical samples. The results show that the decreasing rate of fatigue strength from 400â¯Â°C to 500â¯Â°C is higher than that from 25â¯Â°C to 400â¯Â°C. The fatigue strength coefficient of S-N curve fitted with the Basquin relationship decreases from 25â¯Â°C to 400â¯Â°C and increases from 400â¯Â°C to 500â¯Â°C; while the fatigue strength exponent performs in an inverse tendency. These are resulted from plastic deformation mode transition of the ferrite at the tip of the crack induced by the graphite debonding: slip band at 25â¯Â°C and 400â¯Â°C to grain boundary sliding at 500â¯Â°C. Finally, the influences of carbide on fatigue properties were discussed.
Related Topics
Physical Sciences and Engineering
Engineering
Mechanical Engineering
Authors
Y. Qiu, J.C. Pang, M.X. Zhang, C.L. Zou, S.X. Li, Z.F. Zhang,