梯度堆焊合金层界面组织特征及性能

Interface phase characteristics and properties of gradient hardfacing alloys

在Q235A基体上采用药芯焊丝埋弧焊和自保护明弧焊方式,依次堆焊包含"20Cr2Mn12Ni Mo N韧性过渡层+Cr12W3Mn塑性缓冲层+Cr20Ti Mn Si高铬耐磨层"结构的堆焊合金。借助光学显微镜、扫描电镜、X线衍射仪和显微硬度计等研究堆焊合金层的界面组织特征及性能。结果表明,增加韧性过渡层和塑性缓冲层形成了梯度硬度结构的堆焊合金层,不仅可减小残余应力,而且抑制母材成分的稀释影响,规避网状碳化物和共晶等脆性组织形成。

A hardfacing alloy containing 20Cr2Mn12 Ni Mo N ductile transition layer,Cr12W3 Mn buffer layer and Cr20 Ti Mn Si high-chromium wear-resisting layer was deposited on Q235 base metals by the method of flux-cored wire submerged arc welding and self- shielded open arc welding. The characteristics and the properties of interface phase were researched by optical microscopy（OM）,scanning electron microscopy（SEM）,X-ray diffraction（XRD）and micro-hardness tester. The results show that a gradient hardfacing alloy layer can be made by depositing a ductile transition alloy layer on base metals as well as a buffer alloy layer. The residual stress can be reduced. The dilution effect of base metal on wear-resisting layer composition can be restrained and brittle phases such as reticular carbides and the eutectic can be refrained from the hardfacing alloy layer.