Substrate, a typical ultra-slender aluminum alloy structural components with a large aspect ratio and complex internal structure, was traditionally manufactured by re-assembly and sub-welding. In order to realize the ...Substrate, a typical ultra-slender aluminum alloy structural components with a large aspect ratio and complex internal structure, was traditionally manufactured by re-assembly and sub-welding. In order to realize the monoblock casting of the substrate, the Pro/E software was utilized to carry out three-dimensional(3D) modeling of the substrate casting, and the filling and solidification processes were calculated, as well as the location and types of casting defects were predicted by the casting simulation software Anycasting. Results of the filling process simulation show that the metal liquid is distributed into each gap runner evenly and smoothly. There is no serious vortex phenomenon in the mold cavity, and the trajectory of the virtual particles is clear. Results of the solidification process simulation show that shrinkage cavities mainly appear at the junction of gap runners and the rail surface of the substrate. The average deformation is 0.6 mm in X direction, 3.8 mm in Y direction, and 8.2 mm in Z direction. Based on the simulation results, the casting process of the substrate was optimized, and qualified castings were successfully produced, which will provide a reference for the casting process design of other ultraslender aluminum alloy structural components.展开更多
The counter-gravity casting methods have been developed to remove the casting defects of Mg based alloys. However, the effects of different counter-gravity casting methods on the microstructure and mechanical properti...The counter-gravity casting methods have been developed to remove the casting defects of Mg based alloys. However, the effects of different counter-gravity casting methods on the microstructure and mechanical properties have not been studied in detail. ZM5 alloys were prepared by gravity casting, low-pressure casting and counter-pressure casting, respectively. The mechanical properties, microstructure and fracture morphologies were examined and compared by means of optical microscopy, scanning electron microscopy methods and tensile testing. Results show that casting defects such as gas pore, shrinkage porosity and cavity can be eliminated by counter-pressure casting. The grain size of α-Mg is decreased significantly by counterpressure casting. Moreover, the precipitated particles are more uniform and finer in the counter-pressure casting sample. As a result, the mechanical properties of the alloys are greatly improved. The tensile strength and elongation of the samples by counter-pressure casting are 285 MPa and 13.9%, respectively, which are much higher than those of the low pressure casting and gravity casting.展开更多
文摘Substrate, a typical ultra-slender aluminum alloy structural components with a large aspect ratio and complex internal structure, was traditionally manufactured by re-assembly and sub-welding. In order to realize the monoblock casting of the substrate, the Pro/E software was utilized to carry out three-dimensional(3D) modeling of the substrate casting, and the filling and solidification processes were calculated, as well as the location and types of casting defects were predicted by the casting simulation software Anycasting. Results of the filling process simulation show that the metal liquid is distributed into each gap runner evenly and smoothly. There is no serious vortex phenomenon in the mold cavity, and the trajectory of the virtual particles is clear. Results of the solidification process simulation show that shrinkage cavities mainly appear at the junction of gap runners and the rail surface of the substrate. The average deformation is 0.6 mm in X direction, 3.8 mm in Y direction, and 8.2 mm in Z direction. Based on the simulation results, the casting process of the substrate was optimized, and qualified castings were successfully produced, which will provide a reference for the casting process design of other ultraslender aluminum alloy structural components.
基金financially supported by the Shanghai Sailing Program(Grant No.18QB1401400)the Science Foundation for the Excellent Youth Scholars of Jiangsu Province
文摘The counter-gravity casting methods have been developed to remove the casting defects of Mg based alloys. However, the effects of different counter-gravity casting methods on the microstructure and mechanical properties have not been studied in detail. ZM5 alloys were prepared by gravity casting, low-pressure casting and counter-pressure casting, respectively. The mechanical properties, microstructure and fracture morphologies were examined and compared by means of optical microscopy, scanning electron microscopy methods and tensile testing. Results show that casting defects such as gas pore, shrinkage porosity and cavity can be eliminated by counter-pressure casting. The grain size of α-Mg is decreased significantly by counterpressure casting. Moreover, the precipitated particles are more uniform and finer in the counter-pressure casting sample. As a result, the mechanical properties of the alloys are greatly improved. The tensile strength and elongation of the samples by counter-pressure casting are 285 MPa and 13.9%, respectively, which are much higher than those of the low pressure casting and gravity casting.
