Effect of Boronizing on the High Temperature Mechanical Behavior of Inconel 625

Abstract Inconel 625 is a frequently used material specifically in the exhaust and piping components of gas turbine engines, because of its good corrosion resistance even at high temperatures. In this work, the effect of boronizing on the room and high temperature tensile behavior of Inconel 625 alloy was investigated. According to the room temperature tensile test results, yield strength (YS) and ultimate tensile strength (UTS) of the samples reduced after boronizing. This strength reduction may be attributed to the softening of the material throughout the boronizing process at a high temperature of 1100°C. On the other hand, ductility of the Inconel 625 samples decreased. At elevated temperature, the yield strength of the boronized sample significantly reduced because of the possible decomposition of boron particles throughout tensile straining at elevated temperatures. Consequently, the fracture morphology observations revealed that the main fracture mechanism of both coated and uncoated conditions at high temperature was ductile fracture represented by coarse and deep dimples.