【摘要】 采用等离子喷焊在厚度为1mm的气门锥面制备了3种不同成分的司太立钴基合金喷焊层,采用金相系统观察了焊层的组织形貌,用X射线、电子探针分析了焊层的相结构和成分,测试了焊层的硬度与热稳定性。结果表明,司太立4号喷焊层的组织以细枝晶为主,而司太立6号与司太立F号喷焊层则呈胞状组织。3种合金喷焊层都具有较高的硬度,其中,司太立4号的硬度最高,达到806HV。基材对喷焊层的稀释率低,3种合金的喷焊稀释率都在2%~4%之间。更多还原

【Abstract】 Co-based series alloy coatings with 3 different compositions were prepared respectively on the 1 mm-thick tape-face valve by the plasma spraying welding, and the morphology of coatings were observed. The phase structures of the coatings were determined by X-ray diffraction (XRD) ,the compositions of the coatings were analyzed by the electron probe ,the hardness and the thermal stability of the coatings were conducted. The results showed that the structure of the coating was made mainly up of slender pine-tree crystals for the Stellite 4, and cellular structure for the Stellite 6 and Stellite F. The three alloy coatings had high hardness and the Stellite 4 was the highest one, which was up to 806 HV. The ratio of dilution of the spray welding layer was a-bout 2% to 4% for the three alloys.更多还原