铁基合金粉末中碳化硼添加量对喷焊层性能的影响

Effection of Boron Carbide Content in Iron-based Alloy on the Performance of Spray Welding Layers

为了提高铁基合金喷焊层的硬度与耐磨性,在铁基合金粉末中加入不同含量的碳化硼,采取火焰喷焊技术在42CrMo合金钢表面制备四种复合粉末喷焊层,然后用光学显微镜对喷焊层的显微组织进行分析,利用自动转塔显微硬度计、磨粒磨损试验机测定了喷焊层的显微硬度和耐磨性。实验结果表明:铁基喷焊层与基体形成了良好的冶金结合,涂层主要由细小的树枝晶及鱼骨状共晶组织组成;B4C的加入可显著提高喷焊层的硬度和耐磨性,细化组织,随着B4C含量的增加,喷焊层的硬度和耐磨性呈现先增加,后降低的趋势,当B4C含量为2%时,喷焊层的硬度和耐磨性最好。

In order to improve the hardness and wear resistance of iron base alloy spray welding layer , iron base alloy powder added different content of B4 C and take the flame spray welding technique to prepare four kinds of composite powder spray welding layer on the surface of 42CrMo alloy steel , then use optical microscope , analysis the spray welding layer microstructure , using the automatic turret microhardness me-ter , abrasive wear tester determine of the microhardness and wear resistance of spray welding layer .The experimental results show that Iron base spray welding layer and substrate form a good metallurgical bond-ing ;coating is mainly composed of fine dendrites and herringbone eutectic organization;the addition of B 4 C can significantly increase the hardness and wear resistance of spray welding layers ,refine the organization , with the increase of content of B4 C , hardness and wear resistance of spray welding layer increases first and decrea-ses after trend , when the B4 C content is 2% , hardness and wear resistance of spray welding layer is best .