Study on Exfoliation Resistance of Ferro Superalloy Composite Oxide Scale

Abstract

Based on ferro based superalloy K273 and heat resistant steel ZG40Cr24, test alloys were cast by intermediate frequency induction furnace with non-oxidation method by alloying of aluminium and silicon. The oxidation resistance at 1100°C for 500 hours of test alloys was carried out according to oxidation weight gain method. Experimental results show that the scale exfoliation resistance of K273 and ZG40Cr24 is reinforced greatly by Al2O3 and SiO2. The scale exfoliation weight gain rate at 1100°C descends from 1.2681g.m-2.h-1 to zero, reaching complete exfoliation resistance for ZG40Cr24 test alloy. Because of 1.5<PBR(Al2O3⁄Fe)<2 and the growing of Al2O3 and SiO2 from out side of scale-scale/oxygen interface, the composite scale grows intact and compact without accumulation of growing stress.

Effect of Mn addition on microstructure and mechanical properties of GX40CrNiSi25-12 austenitic heat resistant steel

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Heat resistant steel is widely used in high-temperature working environments in industrial fields such as electric power, petroleum, chemical industry and automotive due to its advantages of excellent high-temperature performance, good oxidation resistance and stress corrosion resistance [1][2][3] . However, the rapid development of industry has put forward higher requirements for the performance of heat resistant steels.

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