42CrMoV紧固件用钢显微组织及夹杂物的分析

Analysis research on microstructure and inclusions of 42CrMoV bolt

摘要: 采用扫描电镜、扫描透射电子显微镜暗场成像、ASPEX软件等研究分析42CrMoV紧固件显微组织及夹杂物.42Cr MoV紧固件基体组织为回火索氏体,基体组织仍保留着原来马氏体的形态,碳化物成排地在晶内和板条边界析出,并且晶界明显多于晶内析出;显微硬度HV0.2为330,奥氏体晶粒度(等级)为9级;夹杂物主要类型为MnS夹杂以及与MnS和CAS有关的复合夹杂物,主要夹杂物尺寸小于5μm,A、B、C、D和Ds夹杂物的等级基本都小于等于0.5级.

Abstract: The microscopic structures and inclusion in 42CrMoV bolt were investigated by SEM,STEM and software ASPEX. The results show that the matrix structure of 42CrMoV bolt is tempered sorbite,but still retains the original morphology of martensite. Carbides precipitate and arrange orderly in intracrystalline and lath boundaries,and the amount of precipitated carbides in grain boundaries are more than that in intracrystalline. Besides,the micro-hardness HV0.2 is 330 and the grain size(level) of austenitic is 9. The Mn S and aluminate are the main inclusion types in 42CrMoV bolt,and the size of inclusions are mostly less than 5 μm,the level of A,B,C,D and Ds inclusion was basically less than or equal to Level 0.5.