Bao Chonggao,Gao Yimin,Xing Jiandong,Zhang Guoshang,Zhu Jinhua
(School of Material Science and Engineering,Xi'an Jiaotong University,Xi'an 710049,China)
Abstract:The erosioncorrosion tester with high speed of liquid-solid two-phase flow was used to simulate different wearing conditions.The erosion-wear resistance of the newly developed 28Cr cast iron was investigated with varying erosion velocities, and the strain hardening mechanism of the austenitic matrix of the iron was emphatically discussed. The results show that the carbide of 28Cr cast iron can protect the austenitic matrix effectively, and stand against the cutting action from the slurry particles because of its high hardness.The mass loss of the iron at the erosion velocity of 45 m/s is larger than that at 34 m/s. In addition,the relative volume fraction of martensite increases from 16.3% to 42.2% at the velocity of 34 m/s,and to 73.6% at 45 m/s,respectively.It is suggested that the strain hardening, including phase transformation and higher dislocation density,may be another main factor of the excellent wear resistance of the 28Cr cast iron.
Keywords:28Cr cast iron;austenitic matrix;erosionwear;strain hardening