Research on high temperature erosion wear behavior of surface strengthened superalloy for underground coal gasification

Abstract Superalloy is the only utilizable material for underground coal gasification channel joint. In this research, the high temperature gas flow erosion wear behavior of superalloy with strengthened layer by boronizing is systematically investigated, including microstructure and hardness. The results reflect that boronizing process can effectively strengthen the surface of superalloy. The high temperature gas erosion wear testing results indicate that boronized layer on superalloy has obvious effect on protecting matrix from high temperature erosion. GH5188 possesses the best high temperature erosion wear resisitance. Before boronizing, wear mechanism of superalloy GH3536 is surface oxidation with spalling of oxide layer by particles impacting, and wear mechanism of superalloy GH5188 and boronized superalloy GH3536 is irregular micro-cutting by high speed particles.