Inconel-625和Hastelloy X鎳基超合金在高溫之空氣氧化行為

Oxidation Behavior of Superalloys Inconel-625 and Hastelloy X in Dry Air

本研究主要在探討兩種鎳基超合金Inconel-625 （In-625）和Hastelloy X （Has-X）在750 ~1050℃乾空氣下之氧化行為。整體而言，兩種合金之氧化動力學皆遵守二段式抛物線律，顯示固態擴散為合金氧化主要機制。經比較穩定增重區之氧化速率常數（kp）得知，兩種鎳基超合金的氧化速率相近，由顯微結構分析得知，合金氧化後的生成物以Cr2O3為主，並在氧化層表面有少量的MnCr2O4摻雜其上。

The oxidation behavior of two Ni-based superalloys, Inconel-625 (In-625) and Hastelloy X (Has-X) was studied at 750 ~ 1050 ℃ in dry air. The oxidation kinetics of both alloys followed a two-stage parabolic-rate law, indicating that diffusion is the rate-controlling step during oxidation. The steady-state rate constants (kp values) of these two alloys were nearly identical. The scales formed on the two alloys were composed of a heterophasic mixture of mostly Cr2O3 and minor MnCr2O4.