氧乙炔火焰喷焊合金层组织与性能的试验研究

Study on microstrcture and performance of oxy-acetylene flame spray-welding alloy layers

利用火焰喷焊法在16Mn钢表面得到铁基合金喷焊层和镍基合金喷焊层,并对两种合金层进行了显微组织、X射线衍射、硬度和腐蚀介质下的耐磨性以及热疲劳性能试验。结果表明,上述两种合金层组织都具有亚共晶型枝晶生长特征,但铁基合金层枝晶发达,镍基合金层枝晶细小均匀。合金喷焊层均由γ固溶体和各种化合物硬质相所组成。焊态时镍基合金层比铁基合金层的硬度和耐磨性高,时效处理后铁基合金层的硬度和耐磨性都明显增加,镍基合金层却略有降低;合金喷焊层在HCl介质中的耐磨性小于在中性水中的耐磨性。镍基合金层比铁基合金层具有较好的抗热疲劳性能;时效处理能改善合金层的抗热疲劳性能。

Fe-based and Ni-based self-melting alloy powders were spray-welded to make the Fe-based and Ni-based alloy layers(Fe55 and Ni60) by oxy-acetylene flame on the 16Mn steel substrate. The microstructure, phases, hardness and wear resistance and thermal fatigue resistance of the layers have been studied. Result showed that the microstructure of alloy layers is consisted of dendritic y solid solution and the fine eutectic structure between the dendrites, and constituted phases are r phase and some compounds. The hardness and wear resistance of Ni60 is higher than Fe55. The hardness and wear resistance of tempered Fe55 is obviously increased, and tempered Ni60 is lightly decreased. Thermal fatigue property of Ni60 is better than Fe55. Temper treatment contributes to improve the thermal fatigue performance of the layers.