高铬白口铸铁耐磨性和显微组织的关系

研究了高铬白口铸铁亚临界热处理后耐磨性和显微组织的关系。结果表明，高铬铸铁在亚临界热处理过程中C和Cr以M23C6型二次碳化物的形式析出，导致奥氏体Ms点升高，使其在冷却时发生马氏体转变。马氏体的高硬度改善了合金耐磨性。合金耐磨性和合金组织中残留奥氏体含量具有相互对应关系，本试验中此含量为10％左右。当残留奥氏体含量低于10％时，由于（Fe，Cr）23C6发生向M3C型碳化物的原位转变，相应的组织转变为珠光体，导致耐磨性急剧下降。

Relationship Between Wear Resistance and Microstructure of High Chromium White Cast Iron

The relationship between wear resistance and microstructure of high chromium white cast iron was studied.The results show that the wear resistance is improved due to austenite transforming into martensite after sub-critical heat treatment.There is coincidence relation between wear resistance and retained austenite content in the cast iron.And the optimal wear resistance corresponds with certain retained austenite content.It is about 10% under the experimental condition.When the retained austenitic content is lower than 10%,the wear resistance will be reduced greatly due to in situ transformation of (Fe,Cr)_(23)C_6 to M_3C and pearlitic structure forming.