Study On The High-Temperature Oxidation Characteristics Of Intermetallic Compounds Cladding Layers

Ni-Al and Mo-Si-Ni-Al intermetallic composite cladding layers were in-situ fabricated on OCr18Ni9 austenitic stainless steel substrate by the means of argon tungsten-arc welding process (GTAW). Microstructure and high-temperature oxidation behavior of both cladding layers were analyzed by the XRD, SEM, and EDS. The results show that the Ni-Al intermetallic composite cladding layer were composed ofβ-NiAl and Ni3Al phase, the average micro-hardness was 500HV0.5; for the Mo-Si-Ni-Al system, there were three main phases, including:β-NiAl, Mo(Si,Al)2 and FeMoSi, the highest micro-hardness is up to 1100HV0.5. The both cladding layers possess good high-temperature oxidation resistance, the oxide scales were dense and integrity. The high-temperature oxidation weight gain curves indicate that the oxidation kinetics of Ni-Al cladding layer at 850℃and 1000℃, Mo-Si-Ni-Al at 1000℃,1100℃and 1200℃were basically satisfied with the parabolic law.