Study on Austempering Process Parameters of Modified Low Chromium White Cast Iron

The effects of austempering process parameters on the mechanical character of modified low chromium white cast iron were studied by orthogonal test. The results show that,when the heating-up temperature is lower or the holding time is shorter,with the increase of holding time or the increase of heating-up temperature,the hardness and the impact toughness of modified low chromium white cast iron increase first and then decrease. The hardness and the impact toughness of the complex phase which composed of lower bainite,martensite and retained austenite are higher than that of lower bainite. When the austempering time is given,the effect order of them on the hardness and the impact toughness is heating-up temperature,holding time and iso-quenching temperature.