摘要
对高碳高铬钢进行激光熔凝处理,采用XRD、OM、SEM及EPMA等分析手段对激光熔凝处理后的组织、物相组成、硬度等进行了研究。结果表明:激光熔凝处理明显改善了高铬钢中网状碳化物的分布状态,组织明显细化,熔凝层组织形态由表及里为等轴晶、树枝晶、胞状晶,显微组织为奥氏体,枝晶间析出少量碳化物;对流传质作用促使激光熔凝层中各元素宏观分布均匀,枝晶间析出细小的富含铬、钼、钒等元素的碳化物;熔凝层由于生成大量的奥氏体,硬度稍有降低,显微硬度最大值出现在热影响区,可达到759 HV。
Laser melting was performed on high-C high-Cr steel. The structure, phase composition and hardness of the high-Cr C steel after laser melting were studied by means of XRD, OM, SEM and EPMA. The results show that the laser melting led to the distribution improvement of net carbides and the refinement of grains. The structure of the melted zone consisted of equiaxed grains, dendrite and cellular grains from the surface to the bottom with austenite microstructure and a few carbides precipitated at grain boundaries. Convention resulted in uniform distribution of the alloying elements in the melted zone, but fine carbides rich in Cr, Mo, V elements precipitated along grain boundaries. Microhardness in melted zone was low due of the presence of a high volume fraction of austenite, but the highest hardness of the HAZ could reach 759 HV.
出处
《机械工程材料》
CAS
CSCD
北大核心
2009年第9期76-78,84,共4页
Materials For Mechanical Engineering
基金
山东省自然科学基金资助项目(Y2006F64)
关键词
激光熔凝
高铬钢
显微组织
硬度
laser melting
high Cr steel
microstructure
hardness
