Laser micro cladding deposition manufacturing(Ll CDM) is a newly developed rapid manufacturing method for metals.The Ll CDM technology adopts a novel powder feeding method based on alternating friction and inertia for...Laser micro cladding deposition manufacturing(Ll CDM) is a newly developed rapid manufacturing method for metals.The Ll CDM technology adopts a novel powder feeding method based on alternating friction and inertia force, and this powder feeding method can effectively improve the accuracy and orientation of the powder injection, resulting in a smaller molten pool size and a higher cooling rate of liquid metal.Therefore, the components fabricated by Ll CDM could obtain the finer microstructures and the improved mechanical properties.It is found that the components fabricated by Ll CDM are fully dense free of cracks or pores and exhibit columnar prior b grains with a finer acicular a0 phase microstructure.The microhardness(HV0.2) of the thin-wall component is HV 400–HV 500 in the majority part of the cross section and can reach about HV 850 in the top region.The ultimate tensile strength(UTS) and elongation show insignificant dependence on the testing directions of the tensilespecimens.The UTS is between 1,002 and 1,100 MPa, and the elongation is between 10.0 % and 14.7 %.展开更多
The microstructure and properties of a quarternary Mg-8Er-5Zn-0.5Zr(mass fraction, %) alloy with the low Er/Zn mass ratio of 1.60 were investigated. It is found that despite of the low Er/Zn mass ratio, the microstruc...The microstructure and properties of a quarternary Mg-8Er-5Zn-0.5Zr(mass fraction, %) alloy with the low Er/Zn mass ratio of 1.60 were investigated. It is found that despite of the low Er/Zn mass ratio, the microstructure of the as-prepared alloy is composed of α-Mg, W phase with face-centered cubic structure and long packed stacking ordered(LPSO) phase. As expected, the extruded and annealed alloy possesses high yield stress(310 MPa) and good elongation(14%) at room temperature. The superior mechanical properties can be interpreted in terms of the promising microstructure characteristic of fine α-Mg recrystallized grains embedded with high-density fine lamellar-shaped LPSO phase and block W phase structure.展开更多
基金financially supported by the National Natural Science Foundation of China (No. 50975152)
文摘Laser micro cladding deposition manufacturing(Ll CDM) is a newly developed rapid manufacturing method for metals.The Ll CDM technology adopts a novel powder feeding method based on alternating friction and inertia force, and this powder feeding method can effectively improve the accuracy and orientation of the powder injection, resulting in a smaller molten pool size and a higher cooling rate of liquid metal.Therefore, the components fabricated by Ll CDM could obtain the finer microstructures and the improved mechanical properties.It is found that the components fabricated by Ll CDM are fully dense free of cracks or pores and exhibit columnar prior b grains with a finer acicular a0 phase microstructure.The microhardness(HV0.2) of the thin-wall component is HV 400–HV 500 in the majority part of the cross section and can reach about HV 850 in the top region.The ultimate tensile strength(UTS) and elongation show insignificant dependence on the testing directions of the tensilespecimens.The UTS is between 1,002 and 1,100 MPa, and the elongation is between 10.0 % and 14.7 %.
基金Project(51171120)supported by the National Natural Science Foundation of China
文摘The microstructure and properties of a quarternary Mg-8Er-5Zn-0.5Zr(mass fraction, %) alloy with the low Er/Zn mass ratio of 1.60 were investigated. It is found that despite of the low Er/Zn mass ratio, the microstructure of the as-prepared alloy is composed of α-Mg, W phase with face-centered cubic structure and long packed stacking ordered(LPSO) phase. As expected, the extruded and annealed alloy possesses high yield stress(310 MPa) and good elongation(14%) at room temperature. The superior mechanical properties can be interpreted in terms of the promising microstructure characteristic of fine α-Mg recrystallized grains embedded with high-density fine lamellar-shaped LPSO phase and block W phase structure.
