硬面合金中碳氮析出物的研究

Study on Carbonitride Precipitates in Hardfacing Alloy with Nitrogen Strengthening

硬面合金是利用研制的氮合金自保护硬面药芯焊丝在低碳钢板上堆焊得到.Nb和Ti作为最有效的碳氮合金化元素被加入到硬面合金中.用光学显微镜、扫描电镜、电子探针研究了硬面合金中碳氮析出物形态和组成,并进行了热力学分析,讨论了碳氮析出物对组织的影响.结果表明:硬面合金中的碳氮析出物为分布在晶界和位错上的MX(M=合金元素,X=C、N)复合型碳氮化物,焊态和热处理条件下具有不同的数量和尺寸.初生碳氮析出物在焊缝凝固过程中形成,并具有较大尺寸;细小的二次碳氮析出物能在堆焊热处理后大量弥散析出,对基体产生明显硬化作用.硬面合金中的碳氮析出沿位错和晶界弥散分布,抑制了富Cr析出相的形成并改善耐晶界腐蚀性能.

The hardfacing alloy was deposited onto a low carbon steel substrate by self-shielded arc welding using nitrogen alloying self-shielded hardfacing flux-cored wire.Nb and Ti as the most effective carbonitride alloying elements were added in the hardfacing alloy.Carbonitride in hardfacing alloy was investigated by optical microscopy,scanning microscopy and electron probe microanalyser.The thermodynamics and the effect on the matrix of the formation of carbonitride were discussed.It was revealed that carbonitr...