H2E

Hydrogen embrittlement (HE) presents a critical challenge for materials used in aerospace gas turbines, particularly as the industry explores hydrogen as a fuel source. Building on a previous literary search conducted for Honeywell Aerospace, which highlighted the complexities of HE in hydrogen environments, this study investigates the impact of cooling speeds on metals embrittled in a hydrogen combustion environment. The motivation for this research stems from the "bakeout process," where hydrogen embrittlement may be alleviated by allowing hydrogen to outgas during the cooling phase of engine operation, reducing risks in high-performance turbines. To test this, INC718, a high-strength superalloy used in turbine engines, is exposed to a direct hydrogen fuel stream in a combustor, with a preload applied to exaggerate the embrittlement effect. After exposure, the samples undergo three cooling methods: oil quenching, still air, and convection cooling. The level of embrittlement for each method is analyzed using scanning electron microscopy (SEM) and tensile testing. This research aims to determine if natural cooling processes during engine operation can mitigate HE or if additional measures are needed. The findings will offer insights into the feasibility of hydrogen as a fuel for aerospace engines and guide mitigation strategies for hydrogen embrittlement in turbine materials.