摘要
研究了不同热处理条件下,19MnSiAlCr钢中加入Al部分替代Si后的贝氏体转变。选区衍射分析显示,在780、800、820℃加热后于460℃等温,组织中出现条状Fe3C。在780、800、820℃加热和425、400℃等温处理后,都得到BF+M/A岛或BF+残留奥氏体的贝氏体组织。研究表明,渗碳体的析出是因为等温温度过高。粒状贝氏体的出现是由于奥氏体中Si、Al原子没有完全扩散而阻止了碳化物的析出,形成了BF+(M/A、RA)的无碳化物贝氏体。在425℃以下等温,由于Si、Al元素的扩散能力减弱阻止了碳化物的析出,因而只得到无碳化物贝氏体,而且随着等温温度的降低,贝氏体含量增加。
Bainite transformation of 19MnSiAlCr steel with high weight percentage of Al partially substitute Si was researched.After heated at 780,800,820 ℃ and isothermally treated at 460 ℃,the selected area diffraction（SAD） analysis show that it is cementite.The microstructure of bainite is composed of BF＋retained austenite and BF＋M/A island after heated at 780,800,820 ℃ and isothermally treated at 425 and 400 ℃.The results show that the reason of cementite formed is that the isothermally bainite temperature is too high.The granular bainite precipitates because the Si,Al atoms do not fully diffuse and can prevent carbide precipitation,thereby forming the BF＋（M/A,RA） carbide-free bainite.Due to weakening of diffusion capacity of Si,Al elements for isothermal temperature below 425 ℃,the amount of bainite increases with the isothermal temperature decreasing.
出处
《金属热处理》
CAS
CSCD
北大核心
2011年第7期32-35,共4页
Heat Treatment of Metals
关键词
贝氏体相变
渗碳体
残留奥氏体
无碳贝氏体
TRIP钢
SI
Al
bainite transformation
cementite
retained austenite
carbide-free bainite
transformation induced plasticity（TRIP） steel
Si
Al
