Ti(C0.3N0.7)/铁基复合耐磨熔覆层激光熔覆

Fe-based alloy composite coating reinforced by Ti(C0.3N0.7)particle through laser cladding technology

关键词:  碳氮化钛  氮化钛  原位反应  激光熔覆

Key words:  Ti(C_0.3N_0.7)particle  TiN particle  in-situ reaction  laser cladding

摘要:

用高能集中的二氧化碳激光束作为诱导热源,在普通低碳钢Q235基材上熔覆了含有碳氮化钛增强粒子的铁基熔覆层,用光镜、扫描电镜、X射线衍射、电子探针等手段对复合熔覆层中的粒子成分、形貌、大小进行了分析,并采用光学显微硬度计对复合熔覆层的显微硬度进行了测试。结果表明,加入的颗粒状TiN与石墨粉在激光熔覆过程中发生了反应,原位生成了新的颗粒状强化相Ti(C_0.3N_0.7)。在熔覆层中Ti(C_0.3N_0.7)的形貌特征多呈尺寸不等近似菱形颗粒及其它不规则形状,大小在0.1~5 μm之间,弥散分布。新Ti(C_0.3N_0.7)颗粒相的生成使得熔覆层得到了强化,熔覆层的显微硬度达到600~700 HV0.2。

Abstract:

A new in-situ synthesis method is carried out to produce Fe-based alloy composite coating reinforced by Ti(C_0.3N_0.7) particle on the Q235 mild steel through CO₂ laser cladding technology.X-ray diffraction is used for phase identification in the composite coating.The microstructure of laser cladding layer is analyzed by means of optical microscopy, scanning electron microscopy, and electron probe microscopy analyzer.The microhardness distribution is measured by using microhardness tester.The results show that Ti(C_0.3N_0.7) particle is produced by an in-situ metallurgical reaction of TiN particle and graphite powder during laser cladding process.The shape of some Ti(C_0.3N_0.7) particle is similar to rhombus, and the others are irregular shape.Size of the fine Ti(C_0.3N_0.7) particles is within 0.1-5 μm, and evenly in dispersed the matrix.The micro-hardness of laser cladding layer is within 600-700 HV0.2, and much higher than that of the matrix.