热处理对大厚壁高铬铸铁Cr27磨损性能的影响

Influence of Heat Treatment on Wear Resistance of High Chromium Cr27 Cast Iron with Heavy Section

采用硬度测量、冲击韧度测试、光学金相及扫描电子显微术,分析了壁厚为90 mm的高铬铸铁件的组织特征及磨损性能。实验结果表明:经过高温等温后淬火,铬的碳化物尺寸明显长大,并随淬火温度的升高而增大。热处理后试样的硬度比铸态明显增加,且随淬火温度的升高,硬度值呈现上升趋势;同时,磨损质量损失相对于铸态试样明显降低,并随淬火温度的升高而减少。对于本实验的高铬铸铁试样,硬度越高,耐磨性能越好。

The mechanical properties and microstructure of high chromium cast iron with heavy section （90 mm thick） were studied by hardness measurement, impact toughness test, OM and SEM. The results show that the size of chromium carbides increases after quenching and the size enhances with the increase of quenching temperature. The hardness values of the heat treatment samples increase compared with the as-cast ones and increase significantly with the increase of quenching temperature. At the same time, wear mass loss decreases after heat treatment processes. With the quenching temperature increasing, the wear mass loss reduces obviously. For the tested high chromium cast iron, the higher hardness of the samples, the better of the wear resistance