The interfacial mold–metal reactions are the main barrier for the development of the magnesium alloy components through the investment casting route, owing to the higher affinity of the magnesium melt with oxygen. The molds are developed with refractory ceramic oxides mainly in the investment casting process. In the present paper, an attempt was made to investigate the influence of the cast part thickness on interfacial mold–metal reactions during the investment casting of AZ91 magnesium alloy. The thermal profiles during the solidification were recorded using the thermocouples and infrared camera. The reactions on the cast surface were quantified and characterized by image analysis, XRD, SEM–EDX and microhardness profile. It was observed that with the increase in thickness, the interfacial mold–metal reaction increases. The surface hardness was also found to be increased with the increase in thickness of the cast part as a consequence of the oxide formation on the cast surface. The reactions on the casting having connected regions of the varying thickness were observed to be relatively more as compared to the casting with the uniform thickness.

由于镁熔体与氧气的亲和力更高，因此界面结晶器与金属的反应是镁合金组件通过熔模铸造工艺发展的主要障碍。主要在熔模铸造工艺中用耐火陶瓷氧化物开发模具。在本文中，试图研究铸件厚度对AZ91镁合金熔模铸造过程中界面结晶器-金属反应的影响。使用热电偶和红外热像仪记录固化过程中的热曲线。通过图像分析，XRD，SEM-EDX和显微硬度分布对铸件表面的反应进行定量和表征。可以观察到，随着厚度的增加，模具与金属之间的界面反应也会增加。还发现由于在铸件表面上形成氧化物，表面硬度随铸件厚度的增加而增加。与具有均匀厚度的铸件相比，观察到在具有变化厚度的连接区域的铸件上的反应相对更多。