A new technology,semi-solid casting(thixocasting) method,was used to replace the conventional hot forging process to form AISI420 stainless steel air-turbine blade.The power law cut-off(PLCO) material model in Procast...A new technology,semi-solid casting(thixocasting) method,was used to replace the conventional hot forging process to form AISI420 stainless steel air-turbine blade.The power law cut-off(PLCO) material model in Procast software was used to simulate the thixocasting process.The thixocasting process was simulated.The results show that the reasonable technology parameters for air-turbine blade thixocasting process are obtained:billet temperature 1 483-1 485 °C,piston velocity 12-15 m/s and die temperature is about 400 °C.展开更多
Along with the recent expansion of demand for electricity, the production of steam turbine blades has increased, and various materials forged of 12Cr ferritic heat-resistant types of steel have become widely used for ...Along with the recent expansion of demand for electricity, the production of steam turbine blades has increased, and various materials forged of 12Cr ferritic heat-resistant types of steel have become widely used for this purpose. Although this material seems to be an excellent choice as heat-resistant steel, it requires a post-correction process for deformation after machining and thus lowers productivity. Therefore, we started basic experimental research, and through a series of tests, we found that 12Cr steel is a sticky material;the residual stresses after machining concentrate in the vicinity of the surface;and this influences the deformation of blades.展开更多
The key manufacturing technologies associated with composition, microstructure, mechanical properties, casting quality and key process control for large martensitic stainless steel castings are involved in this paper....The key manufacturing technologies associated with composition, microstructure, mechanical properties, casting quality and key process control for large martensitic stainless steel castings are involved in this paper. The achievements fully satisfeid the technical requirements of the large 700 MW stainless steel hydraulic turbine runner for the Three Gorges Hydropower Station, and become the major technical support for the design and manufacture of the largest 700 MW hydraulic turbine generator unit in the world developed through our own efforts. The characteristics of a new high yield to tensile strength (R p0.2/R m ) ratio and high obdurability martensitic stainless steel with ultra low carbon and high cleanliness are also described. Over the next ten years, the large martensitic stainless steel castings and advanced manufacturing technologies will see a huge demand in clean energy industry such as nuclear power, hydraulic power at home and abroad. Therefore, the new high yield o tensile strength (R p0.2/R m ) ratio and high obdurability martensitic stainless steel materials, the fast and flexible manufacturing technologies of large size castings, and new environment friendly sustainable process will face new challenges and opportunities.展开更多
基金Project(50375117) supported by the National Natural Science Foundation of China
文摘A new technology,semi-solid casting(thixocasting) method,was used to replace the conventional hot forging process to form AISI420 stainless steel air-turbine blade.The power law cut-off(PLCO) material model in Procast software was used to simulate the thixocasting process.The thixocasting process was simulated.The results show that the reasonable technology parameters for air-turbine blade thixocasting process are obtained:billet temperature 1 483-1 485 °C,piston velocity 12-15 m/s and die temperature is about 400 °C.
文摘Along with the recent expansion of demand for electricity, the production of steam turbine blades has increased, and various materials forged of 12Cr ferritic heat-resistant types of steel have become widely used for this purpose. Although this material seems to be an excellent choice as heat-resistant steel, it requires a post-correction process for deformation after machining and thus lowers productivity. Therefore, we started basic experimental research, and through a series of tests, we found that 12Cr steel is a sticky material;the residual stresses after machining concentrate in the vicinity of the surface;and this influences the deformation of blades.
文摘The key manufacturing technologies associated with composition, microstructure, mechanical properties, casting quality and key process control for large martensitic stainless steel castings are involved in this paper. The achievements fully satisfeid the technical requirements of the large 700 MW stainless steel hydraulic turbine runner for the Three Gorges Hydropower Station, and become the major technical support for the design and manufacture of the largest 700 MW hydraulic turbine generator unit in the world developed through our own efforts. The characteristics of a new high yield to tensile strength (R p0.2/R m ) ratio and high obdurability martensitic stainless steel with ultra low carbon and high cleanliness are also described. Over the next ten years, the large martensitic stainless steel castings and advanced manufacturing technologies will see a huge demand in clean energy industry such as nuclear power, hydraulic power at home and abroad. Therefore, the new high yield o tensile strength (R p0.2/R m ) ratio and high obdurability martensitic stainless steel materials, the fast and flexible manufacturing technologies of large size castings, and new environment friendly sustainable process will face new challenges and opportunities.
