In order to address the urgent demand for lightweight components in the aerospace,a laser-arc hybrid additive manufacturing(LAHAM)is innovatively applied to the Mg-Gd-Y-Zr alloy in this study.The results show that com...In order to address the urgent demand for lightweight components in the aerospace,a laser-arc hybrid additive manufacturing(LAHAM)is innovatively applied to the Mg-Gd-Y-Zr alloy in this study.The results show that compared with wire arc additive manufacturing(WAAM),the grain size and texture strength of LAHAM were reduced by about 26% and 27% respectively.The β phase at grain boundaries are effectively mitigated.In LAHAM,the nanoscale β phase(Mg_(24)(Gd,Y)_(5)+Mg_(5)(Gd,Y))and β_(1) phase(Mg_(3)(Gd,Y))were uniformly distributed in the grain boundary.There were only nanoscale β phase distributed around the enriched second phase in WAAM.The size and type of nanoparticles directly affect the mechanical properties of alloys.The tensile strength and yield strength of WAAM specimen were about 228 MPa,152 MPa.Compared with WAAM,the tensile strength and yield strength of LAHAM were increased by about 12% and 15%,reaching 254 MPa and 175 MPa.The contribution of precipitation strengthening is about 42%.This study provides a new perspective for the systematic application and fabrication of Mg-Gd-Y-Zr alloy.展开更多
The normal T6 heat treatment process for cast A356 alloy generally requires about 15 h. This longperiod procedure increases greatly the manufacturing cost and decreases the productivity in practical production. In thi...The normal T6 heat treatment process for cast A356 alloy generally requires about 15 h. This longperiod procedure increases greatly the manufacturing cost and decreases the productivity in practical production. In this study, a new short-time heat treatment process with only 30 min solution time at 540℃ was developed for the production of motorcycle wheel hubs in order to reduce heat treatment time. Comparisons on microstructure evaluation and mechanical properties, such as tensile strength and ductility, were made between this new fast process and the conventional T6 heat treatment. The results revealed that this new heat treatment process enabled the spheroidization of the eutectic silicon thoroughly, while minimizing the growth of eutectic silicon. The A356 alloy after this new short-time heat treatment shows nearly equal mechanical properties compared with the same alloy heat treated in a normal T6 heat treatment. This investigation makes it possible to significantly improve the efficiency of heat treatment on A356 alloy and, at the same time, improve the mechanical properties of the alloy.展开更多
基金the financial support from the National Key Research and Development Program(No.2023YFB4606004 and No 2023YFB4606002)the Fundamental Research Funds for the Central University(No.DUT21YG116).
文摘In order to address the urgent demand for lightweight components in the aerospace,a laser-arc hybrid additive manufacturing(LAHAM)is innovatively applied to the Mg-Gd-Y-Zr alloy in this study.The results show that compared with wire arc additive manufacturing(WAAM),the grain size and texture strength of LAHAM were reduced by about 26% and 27% respectively.The β phase at grain boundaries are effectively mitigated.In LAHAM,the nanoscale β phase(Mg_(24)(Gd,Y)_(5)+Mg_(5)(Gd,Y))and β_(1) phase(Mg_(3)(Gd,Y))were uniformly distributed in the grain boundary.There were only nanoscale β phase distributed around the enriched second phase in WAAM.The size and type of nanoparticles directly affect the mechanical properties of alloys.The tensile strength and yield strength of WAAM specimen were about 228 MPa,152 MPa.Compared with WAAM,the tensile strength and yield strength of LAHAM were increased by about 12% and 15%,reaching 254 MPa and 175 MPa.The contribution of precipitation strengthening is about 42%.This study provides a new perspective for the systematic application and fabrication of Mg-Gd-Y-Zr alloy.
基金financially supported by the National Natural Science Foundation of China under project 51574129
文摘The normal T6 heat treatment process for cast A356 alloy generally requires about 15 h. This longperiod procedure increases greatly the manufacturing cost and decreases the productivity in practical production. In this study, a new short-time heat treatment process with only 30 min solution time at 540℃ was developed for the production of motorcycle wheel hubs in order to reduce heat treatment time. Comparisons on microstructure evaluation and mechanical properties, such as tensile strength and ductility, were made between this new fast process and the conventional T6 heat treatment. The results revealed that this new heat treatment process enabled the spheroidization of the eutectic silicon thoroughly, while minimizing the growth of eutectic silicon. The A356 alloy after this new short-time heat treatment shows nearly equal mechanical properties compared with the same alloy heat treated in a normal T6 heat treatment. This investigation makes it possible to significantly improve the efficiency of heat treatment on A356 alloy and, at the same time, improve the mechanical properties of the alloy.
