Experimental study reveals temperature-driven recrystallization in laser-melted GH3536 superalloy, indicating that elevated heat treatment significantly enhances ductility.
Key Points
Investigate how heat-treatment temperatures between 980 °C and 1280 °C affect the microstructure, precipitate evolution, and mechanical performance of selective-laser-melted GH3536 superalloy.
Subjected selective-laser-melted GH3536 nickel-based superalloy specimens to 1-hour heat treatments at temperatures ranging from 980 °C to 1280 °C.
Tracked microstructural changes, including carbide dissolution, grain morphology, aspect ratios, and recrystallization kinetics.
Evaluated mechanical behavior through Vickers hardness measurements and tensile property testing.
Exposure to 1180 °C completely dissolved grain-boundary Mo-rich M6C carbides into the matrix and yielded a 49.7% recrystallized fraction, which increased to 89.8% with 40.8 µm grain size at 1280 °C.
Hardness decreased progressively from 251.8 ± 13.5 HV in the as-built alloy to 176.3 ± 5.5 HV after treatment at 1280 °C due to sequential recovery and recrystallization.
Specimens treated at 1280 °C exhibited a tensile elongation of 67.4%, demonstrating exceptional grain boundary thermal stability and interfacial bonding strength despite lowered yield strength.