钼对含铌低合金铸钢碳化物析出行为的影响  

Effects of Mo Contents on Carbide Precipitation Behavior of Low-Alloyed Cast Steel with Microalloyed Nb

作　　者：刘腾轼 杨弋涛[1] 

机构地区：[1]上海大学材料科学与工程学院,上海200072

出　　处：《铸造》2015年第1期60-64,共5页Foundry

摘　　要：借助熔炼制备合金的方法以及OM、SEM、TEM、碳化物萃取及XRD研究了含铌低合金铸钢中Mo的添加对碳化物析出行为的影响。结果表明:随Mo含量增加,组织由多边形铁素体向针状铁素体转变,片状珠光体向粒状贝氏体转变;铁素体晶粒内弥散析出的颗粒状和随机分布的短杆状碳化物增加,纽扣锭试样的硬度、强度增加,塑性降低。碳化物萃取及XRD衍射分析发现,试样中碳化物质量分数随Mo含量增加而增加;在1#Ori试样中碳化物主要为Fe3C、(Fe,Mn)3C型合金渗碳体及弥散析出的Nb(C,N)颗粒;在2#Mo、3#Mo试样中有Mo2C、Nb(C,N)和Mo(C,N)型碳化物析出。The influences of Mo contents on carbide precipitation behavior of the containing Nb low-alloyed cast steel were investigated by means of the vacuum arc furnace, OM, SEM, TEM, carbide extraction and XRD. The results show that with the increase of Mo content, polygonal ferrite has transformed to acicular ferrite, and lamellar pearlite has transformed to granular bainite. Granular carbides which precipitated dispersedly in the crystal of fcrrite and the short rod carbides which distribute randomly have also increased, and the hardness, strength of button ingot has been raised while the ductility has been descended. According to the result of the carbide extraction and XRD phase analysis, the weight percentage of carbide has been increased with the rise of Mo contents. The types of carbides in the 1^#Ori sample are Fe3C, （Fe, Mn）3C and Nb（C, N） which is granular precipitated dispersedly. In 2^#Mo, 3^#Mo sample, Mo2C and （Mo, Nb）（C, N） carbides are precipitated.

关 键 词：合金元素 显微组织 析出强化 碳化物 

分 类 号：TG142.1[一般工业技术—材料科学与工程]