This study investigates the susceptibility of hot cracking and weldment heat treatment of Haynes 230 superalloy. The Varestriant test was conducted to evaluate this susceptibility. Welding was performed by gas tungste...This study investigates the susceptibility of hot cracking and weldment heat treatment of Haynes 230 superalloy. The Varestriant test was conducted to evaluate this susceptibility. Welding was performed by gas tungsten arc welding （GTAW） and plasma arc welding （PAW） with stress relief heat treatment and solid solution heat treatment. A tensile test is then performed to measure the changes in the mechanical properties of the heattreated material. The results indicate that the number of thermal cycles does not affect the susceptibility of Haynes 230 superalloy to hot cracking. However, it does increase the strain. In weldment of heat treatment, stress relief annealing increases the yield strength and tensile strength of the welded parts. The section of the tensile specimens shows fibrous fractures on the welded parts, regardless of whether they are heat-treated.展开更多
To predict the microstructure evolution and reveal the forming mechanism of Ni-based superalloy cylindrical parts during hot power spinning, a finite element method (FEM) model of deformation-heat transfermicrostructu...To predict the microstructure evolution and reveal the forming mechanism of Ni-based superalloy cylindrical parts during hot power spinning, a finite element method (FEM) model of deformation-heat transfermicrostructure evolution was established using MSC.Marc software. A numerical simulation was then conducted based on the secondary development of user subroutines, to investigate evolution of the microstructure of a Haynes 230 alloy cylindrical part during hot power spinning. The volume fraction of dynamic recrystallization (DRX) and the grain size of Haynes 230 alloy cylindrical parts during hot power spinning were analyzed. The results showed that the DRX of the spun workpiece was more obvious with an increase in the forming temperature, T, and the total thinning ratio of wall thickness,ψt.Furthermore, the complete DRX microstructure with fine and uniform grains was obtained when T≥1 100 °C and ψt≥ 2 56%, but the grain size of the spun workpiece decreased slightly with an increase in the roller feed rate, f. The experimental results conformed well with simulation results.展开更多
文摘This study investigates the susceptibility of hot cracking and weldment heat treatment of Haynes 230 superalloy. The Varestriant test was conducted to evaluate this susceptibility. Welding was performed by gas tungsten arc welding （GTAW） and plasma arc welding （PAW） with stress relief heat treatment and solid solution heat treatment. A tensile test is then performed to measure the changes in the mechanical properties of the heattreated material. The results indicate that the number of thermal cycles does not affect the susceptibility of Haynes 230 superalloy to hot cracking. However, it does increase the strain. In weldment of heat treatment, stress relief annealing increases the yield strength and tensile strength of the welded parts. The section of the tensile specimens shows fibrous fractures on the welded parts, regardless of whether they are heat-treated.
基金the National Natural Science Foundation of China (Grant Nos. 51375172, 51775194)Specialized Research Fund for the Doctoral Program of Higher Education (SRFDP)(Grant No. 20130172110024)+1 种基金Guangdong Provincial Key Laboratory of Precision Equipment and Manufacturing Technology (PEMT1202)the EU Marie Curie Actions - MatProFuture Project (FP7-PEOPLE-2012-IRSES-318968).
文摘To predict the microstructure evolution and reveal the forming mechanism of Ni-based superalloy cylindrical parts during hot power spinning, a finite element method (FEM) model of deformation-heat transfermicrostructure evolution was established using MSC.Marc software. A numerical simulation was then conducted based on the secondary development of user subroutines, to investigate evolution of the microstructure of a Haynes 230 alloy cylindrical part during hot power spinning. The volume fraction of dynamic recrystallization (DRX) and the grain size of Haynes 230 alloy cylindrical parts during hot power spinning were analyzed. The results showed that the DRX of the spun workpiece was more obvious with an increase in the forming temperature, T, and the total thinning ratio of wall thickness,ψt.Furthermore, the complete DRX microstructure with fine and uniform grains was obtained when T≥1 100 °C and ψt≥ 2 56%, but the grain size of the spun workpiece decreased slightly with an increase in the roller feed rate, f. The experimental results conformed well with simulation results.
