Effect of grit blasting and subsequent heat treatment on stress rupture property of a Ni-based single-crystal superalloy SGX3
来源期刊：Acta Metallurgica Sinica2020年第12期
论文作者：Jinshan He Zhengrong Yu Longfei Li Xitao Wang Qiang Feng
摘 要：In the present study, the effect of grit blasting and subsequent heat treatment on the stress rupture properties of a thirdgeneration nickel-based single-crystal superalloy SGX3 sheet was studied. It was found that the stress rupture life of alloy SGX3 sheet at 980 °C/250 MPa was reduced by about 60% by only vacuum heat treatment at 1100 °C for 200 h and further reduced by 20% and 70% respectively with grit blasting of 0.3 MPa/1 min and 0.5 MPa/2 min before heat treatment. The microstructure analysis results indicated that the degradation of stress rupture life of alloy SGX3 sheet by vacuum heat treatment was mainly attributed to the variation of γ/γ′ microstructure, i.e., the decrease in γ′ volume fraction and the coarsening of γ′ precipitates. Furthermore, such degradation by grit blasting and subsequent vacuum heat treatment should be attributed to the formation of cellular recrystallization with different thicknesses at the surface of alloy SGX3 sheet, which not only acts as the vulnerable site for cracks to initiate and propagate but also reduces the effective loading area.
Jinshan He1，Zhengrong Yu2，Longfei Li2，Xitao Wang1,3，Qiang Feng2
1. Beijing Advanced Innovation Center for Material Genome Engineering,Collaborative Innovation Center of Steel Technology ,University of Science and Technology Beijing2. Beijing Advanced Innovation Center for Material Genome Engineering,State Key Laboratory for Advanced Metals and Materials ,University of Science and Technology Beijing3. Shandong Provincial Key Laboratory for High Strength Lightweight Metallic Materials,Advanced Materials Institute ,Qilu University of Technology (Shandong Academy of Sciences)
摘 要：In the present study, the effect of grit blasting and subsequent heat treatment on the stress rupture properties of a thirdgeneration nickel-based single-crystal superalloy SGX3 sheet was studied. It was found that the stress rupture life of alloy SGX3 sheet at 980 °C/250 MPa was reduced by about 60% by only vacuum heat treatment at 1100 °C for 200 h and further reduced by 20% and 70% respectively with grit blasting of 0.3 MPa/1 min and 0.5 MPa/2 min before heat treatment. The microstructure analysis results indicated that the degradation of stress rupture life of alloy SGX3 sheet by vacuum heat treatment was mainly attributed to the variation of γ/γ′ microstructure, i.e., the decrease in γ′ volume fraction and the coarsening of γ′ precipitates. Furthermore, such degradation by grit blasting and subsequent vacuum heat treatment should be attributed to the formation of cellular recrystallization with different thicknesses at the surface of alloy SGX3 sheet, which not only acts as the vulnerable site for cracks to initiate and propagate but also reduces the effective loading area.
关键词：
