Oxidation Resistance of a Co-Base Superalloy Improved by Pre-Oxidation Heat Treatment. Issue 6 (1st January 2016)

• Record Type: Journal Article
• Authors: Liu, Longfei; Wu, Shusen; Chen, Yang; Lü, Shulin
• Is Part Of: Journal of the Electrochemical Society. Volume 163:Issue 6(2016)
• Page Start: C282
• Page End: C288
• Publication Date: 2016-01-01
• Subjects: Co-base superalloy -- multi-oxide layers -- oxidation resistance -- pre-oxidation heat treatment; Electrochemistry -- Periodicals; 541.3705
• DOI: 10.1149/2.0511606jes
• Languages: English
• ISSNs: 0013-4651

Abstract

Abstract : The influence of a pre-existing multi-oxide layer on the subsequent re-oxidation at different temperatures of a 22Co-21Ni-23Fe-29Cr-1.6Si-1Mn superalloy was investigated. The pre-oxidation heat-treatment (PHT) at 1200°C for 5 min resulted in the formation of a protective multi-oxide layer. The behavior of pre-treated and non pre-treated samples during isothermal oxidation at 800, 900 and 1000°C in air was studied. Results showed that rate-constants of the oxidation processes of pre-treated samples were significantly lower than those of the non pre-treated ones. Oxidation at 800, 900 and 1000°C in air for 100 h, resulted in the formation of MnCr2 O4, Cr2 O3 and SiO2 compounds for both kinds of samples. A diffusion-controlled mechanism is proposed to describe the oxidation process.