热处理对锰硼白口铁机械性能与显微组织的影响

Effect of Heat Treatment on Mechanical Properties and Microstructure of White Cast Iron Alloyed by Manganese and Borow

研究了淬火、回火温度、冷却介质对锰硼白口铁机械性能及显微组织的影响。结果表明:淬火硬度随淬火温度提高出现峰值,峰值位置随淬火冷却速度增加向温度低的方向移动;回火硬度随回火温度升高在250℃出现峰值,回火温度高于480℃后硬度显著降低;残留奥氏体随回火温度升高而减少,430℃回火残留奥氏体基本消失,转变产物为贝氏体;淬火回火提高强韧性。

The effect of quenching and tempering on mechanical properties and microstructure of white cast Iron alloyed by Mn and B is studied. The results show that the quenching hardness changes following a crest curve with quenching-temperature rise;the slower the cooling rate, the higher the quenching temperature to get crest value; with tempering-temperature rise, the tempering hardness gets crest value at 250℃, and decrease remarkedly when temperature above 480℃; and quenching and tempering improve strength and impact toughness.