为分析原位合成Cr3C2-NiCr金属陶瓷激光沉积层结合区各组织的生成机制，以质量分数为Ni25%-Cr65%-石墨10%能量色散光谱单元素混合粉为原料原位合成激光沉积层，利用光学显微镜、X射线衍射仪、扫描电子显微镜(X射线能谱仪)等手段研究沉积层结合区显微组织特点，结合激光熔池冶金热力学过程，分析结合区显微组织形成机制。结果表明，Cr3C2-NiCr金属陶瓷层主要由Cr3C2、Cr7C3和Ni基固溶体组成，沉积层与45#钢基体的结合区分为共晶区、枝晶区和平面晶区。根据石墨在Cr-Ni熔池中溶解进程，可以得到结合区碳化物的生长过程，即枝晶前沿生长出Ni+M23C6共晶，并包围低熔点合金生长出壳状M7C3碳化物，在熔池中生成Cr3C2-NiCr金属陶瓷。

To analyse the growing mechanism of bond zone in cermet Cr3C2-NiCr coating, which is made through in situ laser deposition, in situ laser deposit coatings is compounded with Ni25-Cr65-graphite10 (mass fraction: %) powder mixture. The bond zone microstructures coatings are studied by optical microscope, X-ray diffraction and scan electron microscope (energy dispersive X-ray detector). Following analysis of the laser melt metallurgical thermodynamics, the growing mechanism of the bond zone microstructures is elucidated. The results show that the bond zone of cermet Cr3C2-NiCr coatings constitutes three different zones: eutectic, dendritic and planar. With the study of the process of graphite dissolution in Cr-Ni laser melt, the growth mechanism of carbides in the bonding zone is revealed. Ni+M23C6 eutectic is formed on the front of the dendrites, the shell-shaped M7C3 grows and surrounds the low melting point alloy, and the cermet Cr3C2-NiCr is generated in laser melt.