Here we fabricate LA103Z Mg-Li alloy via wire-arc directed energy deposition(WA-DED),and subsequent aging treatment is employed to improve its mechanical property.Results show that a typical dual-phase microstructure ...Here we fabricate LA103Z Mg-Li alloy via wire-arc directed energy deposition(WA-DED),and subsequent aging treatment is employed to improve its mechanical property.Results show that a typical dual-phase microstructure is formed upon WA-DED,consisting of α-Mg,β-Li,AlLi and Li_(2)MgAl,with negligible porosity,and the core-shell Li_(2)MgAl/AlLi composite particles are also generated.After aging treatment,the microstructure is slightly coarsened,together with the precipitation of nano-sized D0_(3)-Mg_(3)Al particles,as well as the dissolution and the mergence of α-Mg phases.Negligible strength and ductility anisotropies are found for the as-deposited alloy.Significant strength increment is achieved via aging treatment,and the ultimate strength increases by~20%(~34 MPa),reaching 200±1 MPa.Both as-deposited and aged alloys show acceptable uniform elongation,with a transgranular fracture mode.Precipitation strengthening enabled by nano-sized D0_(3)-Mg_(3)Al precipitates is primarily responsible for the strength increment mediated by aging treatment.Grain refinement strengthening and solid solution strengthening provide additional contributions to the improved strength.Our work thus offers an applicable additive manufacturing pathway for the efficient and safety-guaranteed fabrication of Mg-Li alloy components with decent mechanical property.展开更多
This study pioneers the integrated fabrication of magnesium corrugated-core sandwich structures using wire-arc directed energy deposition(WA-DED).Two sandwich structures—V-type and X-type—were designed with optimize...This study pioneers the integrated fabrication of magnesium corrugated-core sandwich structures using wire-arc directed energy deposition(WA-DED).Two sandwich structures—V-type and X-type—were designed with optimized deposition paths to achieve comparable grain morphology while enhancing strength.The compression properties and failure modes of the two corrugated-core sandwich structures were examined through quasi-static compression tests.Results showed that the V-type structure exhibited a higher specific compressive strength(93 MPa∙cm^(3)/g)than the X-type structure(72 MPa∙cm^(3)/g).Both finite element analysis and experimental compression tests indicated that failure occurred at the midsection of the corrugated core.This work offers valuable insights for the efficient fabrication of high-strength corrugated-core sandwich structures.展开更多
Conventional cast Al-Ce alloys are challenged by the increasing demand for improved mechanical properties.To address this issue,in this study,wire-arc directed energy deposition(WA-DED)is employed for the fabrication ...Conventional cast Al-Ce alloys are challenged by the increasing demand for improved mechanical properties.To address this issue,in this study,wire-arc directed energy deposition(WA-DED)is employed for the fabrication of Al-15Ce-3Mg(wt%)alloy components.We aimed to tune the microstructure and mechanical properties via the inherent sub-rapid-solidification effect of WA-DED.In addition to significant microstructure refinement,a decrease in arc heat input leads to a larger cooling rate,up to 346℃/s,and triggers the transition from hyper-eutectic to near-eutecticα-Al/Al_(11)Ce_(3)microstructures with the suppression of primary Al_(11)Ce_(3)intermetallics.Such microstructural modification improves the mechanical properties,resulting in higher yield and ultimate tensile strengths than those of the as-cast counterpart alloy.The fracture process involves the formation of dim-ples around Al_(11)Ce_(3),cracking of large Al_(11)Ce_(3) particles,and growth,merging,and fracture of pores.The strength increment is mainly contributed by particle-size strengthening mediated by microstructure refinement as well as the targeted formation of near-eutecticα-Al/Al_(11)Ce_(3)microstructures.展开更多
基金supported by the National Natural Science Foundation of China(52475320).
文摘Here we fabricate LA103Z Mg-Li alloy via wire-arc directed energy deposition(WA-DED),and subsequent aging treatment is employed to improve its mechanical property.Results show that a typical dual-phase microstructure is formed upon WA-DED,consisting of α-Mg,β-Li,AlLi and Li_(2)MgAl,with negligible porosity,and the core-shell Li_(2)MgAl/AlLi composite particles are also generated.After aging treatment,the microstructure is slightly coarsened,together with the precipitation of nano-sized D0_(3)-Mg_(3)Al particles,as well as the dissolution and the mergence of α-Mg phases.Negligible strength and ductility anisotropies are found for the as-deposited alloy.Significant strength increment is achieved via aging treatment,and the ultimate strength increases by~20%(~34 MPa),reaching 200±1 MPa.Both as-deposited and aged alloys show acceptable uniform elongation,with a transgranular fracture mode.Precipitation strengthening enabled by nano-sized D0_(3)-Mg_(3)Al precipitates is primarily responsible for the strength increment mediated by aging treatment.Grain refinement strengthening and solid solution strengthening provide additional contributions to the improved strength.Our work thus offers an applicable additive manufacturing pathway for the efficient and safety-guaranteed fabrication of Mg-Li alloy components with decent mechanical property.
基金supported by JCKY Project(Grant No.JCKY2023602B012).
文摘This study pioneers the integrated fabrication of magnesium corrugated-core sandwich structures using wire-arc directed energy deposition(WA-DED).Two sandwich structures—V-type and X-type—were designed with optimized deposition paths to achieve comparable grain morphology while enhancing strength.The compression properties and failure modes of the two corrugated-core sandwich structures were examined through quasi-static compression tests.Results showed that the V-type structure exhibited a higher specific compressive strength(93 MPa∙cm^(3)/g)than the X-type structure(72 MPa∙cm^(3)/g).Both finite element analysis and experimental compression tests indicated that failure occurred at the midsection of the corrugated core.This work offers valuable insights for the efficient fabrication of high-strength corrugated-core sandwich structures.
基金supported by National Natural Science Foundation of China(Grant No.52105319)The authors are grateful to the Analysis&Testing Center and the Micro-and Nanotechnology Center at the Beijing Institute of Technology for performing the XRM experiments.
文摘Conventional cast Al-Ce alloys are challenged by the increasing demand for improved mechanical properties.To address this issue,in this study,wire-arc directed energy deposition(WA-DED)is employed for the fabrication of Al-15Ce-3Mg(wt%)alloy components.We aimed to tune the microstructure and mechanical properties via the inherent sub-rapid-solidification effect of WA-DED.In addition to significant microstructure refinement,a decrease in arc heat input leads to a larger cooling rate,up to 346℃/s,and triggers the transition from hyper-eutectic to near-eutecticα-Al/Al_(11)Ce_(3)microstructures with the suppression of primary Al_(11)Ce_(3)intermetallics.Such microstructural modification improves the mechanical properties,resulting in higher yield and ultimate tensile strengths than those of the as-cast counterpart alloy.The fracture process involves the formation of dim-ples around Al_(11)Ce_(3),cracking of large Al_(11)Ce_(3) particles,and growth,merging,and fracture of pores.The strength increment is mainly contributed by particle-size strengthening mediated by microstructure refinement as well as the targeted formation of near-eutecticα-Al/Al_(11)Ce_(3)microstructures.
