Powder metallurgy superalloy is a key material for hot end components of aero engines,which is usually prepared and formed by sintering-forging process.The sintered sample microstructure(hereinafter referred to as the initial microstructure before forging)has an important influence on the microstructure evolution and mechanical properties of as-forged sample.Based on this,two samples with high and low prior particle boundary(PPBs)defect grades were prepared by hot pressing(HP)sintering technology,and the two samples were treated by hot forging(HF)to study the effect of the initial microstructure on the microstructure and mechanical properties of as-forged samples.The experimental results show that the defect scale of the samples with high PPBs defect grade is significantly reduced after hot forging treatment,and room-temperature ultimate tensile strength and elongation increase from 1220±74MPa and 18.1±3.6% to 1402±3MPa and 26.8±1.5% at,the tensile properties are significantly improved and tend to be stable,and the fracture mode changes from inter-particle fracture to trans-particle fracture.The room-temperature ultimate tensile strength and elongation of the samples with low PPBs defect grade increase from 1209±27MPa and 18.8±1.0% to 1249±3MPa and 24.9±1.5% e,the tensile properties are slightly improved,and the fracture mode changes from inter-particle fracture to inter-particle and trans-particle mixed fracture.
NETL
NSTL
万方数据
