高锰奥氏体钢的碳化物沉淀析出行为

Precipitation behavior of carbides in a high manganese austenitic steel for magnetic liner

根据磁性衬板对奥氏体钢超高硬度的研发需求,在高锰奥氏体钢中添加适量的碳化物形成元素,经热处理的后采用TEM、SEM、XRD等手段研究了固溶时效态高锰奥氏体钢中碳化物的析出行为,以期获得超高硬度奥氏体钢。结果表明:高锰奥氏体钢在固溶时效状态下,组织中均匀析出大量Cr23C6相,其数量在675℃时效时达到饱和,随后开始长大聚集;时效使材料中大量弥散析出约十几纳米的VC颗粒,弥散的VC颗粒与基体间存在共格界面,存在多种共格关系,这种具有共格界面的纳米VC颗粒对材料硬度提高作用非常明显。

A new ultrahigh hardness austenite steel for magnetic lining was developed by addition of a moderate amount of carbide forming elements to commercial high manganese austenitic steel. Precipitation behavior of carbides in the high manganese austenitic steel after heat treatment was analyzed by means of transmission electron microscopy, scanning electron microscopy and XRD. The results show that Cr23C6 phases uniformly precipitate from austenite after solution and aging treatment, and the amount of M23 C6 carbides reaches the maximum value at the aging temperature of 675 ~C. After then the M23C6 phases start to grow up and gather. Large number of dispersed VC particles with tens of nanometers precipitate in the steel during aging treatment, which exhibit coherent interface with matrix, and these precipitated VC particles significantly enhance the hardness of the material.