Mo、Cu对高铬铸铁凝固组织和亚临界热处理硬化行为的影响

Effect of Mo and Cu on Solidification Structure and Hardening Behavior of High Chromium White Cast Iron Subjected to Sub-critical Treatment

研究了Mo和Cu对高铬铸铁凝固组织和亚临界热处理硬化行为的影响。研究表明 ,添加Mo和Cu可以使高铬铸铁的凝固组织获得更多的残留奥氏体。含有Mo和Cu的高铬铸铁在亚临界热处理过程中有明显的二次硬化现象。由于Mo是强碳化物形成元素与碳原子之间有强的相互吸引作用 ,阻碍碳原子在凝固冷却时碳从奥氏体向液相扩散 ,使共晶奥氏体的碳含量较高 ,导致奥氏体的Ms点降低 ,使得铸态组织获得更多的残留奥氏体。固溶于奥氏体中的Cu对奥氏体中碳在亚临界热处理过程中的析出具有很强的阻碍作用 ,所以与没有添加Mo和Cu的高铬铸铁比较 。

The effect of Mo and Cu on the solidification structure and hardening behavior of high chromium white cast iron subjected to sub-critical treatment was studied in this paper.The investigation indicates that adding Mo and Cu can help alloys achieve more retained austenite and less eutectic carbide in the as-cast condition.Alloys have obvious secondary hardening behavior in sub-critical treating process.But the secondary hardening peak occurs at higher temperature or longer holding time compared with that of alloys without Mo and Cu for the inhibitive effect of Mo and Cu which solid-dissolved in austenite on the precipitation of C from austenite during sub-critical treating process.