Hot corrosion behavior of hot isostatic pressing treated TiC/GTD222 composite fabricated by selective laser melting

Abstract

Purpose This paper aims to design a novel TiC/GTD222 nickel-based high-temperature alloy with excellent hot corrosion resistance by incorporating appropriate amounts of C, Al and Ti elements into GTD222 alloy. Design/methodology/approach The composite material was prepared using the selective laser melting (SLM) technology, followed by a hot isostatic pressing (HIP) treatment. Subsequently, the composite underwent a hot corrosion test in a 75% Na2SO4 + 25% NaCl mixed salt environment at 900 °C. Findings The HIP-SLMed TiC/GTD222 composite exhibits a relatively low weight loss rate. First, the addition of alloying elements facilitates the formation of multiple protective oxide films rich in Al, Ti and Cr. These oxide films play a crucial role in enhancing the material’s resistance to hot corrosion. Second, the HIP treatment results in a reduction of grain size in the composite and an increased number of grain boundaries, which further promote the formation of protective films. Originality/value The hot corrosion behavior of the TiC/GTD222 nickel-based composite material prepared through SLM and HIP processing has not been previously studied. This research provides a new approach for designing nickel-based superalloys with excellent hot corrosion resistance.