The effects of Si addition and applied pressure on the microstructure and tensile properties of as-cast Al-5.0 Cu-0.6 Mn-1.2 Fe alloys were studied. The results show that Si addition promotes the formation of Chinese ...The effects of Si addition and applied pressure on the microstructure and tensile properties of as-cast Al-5.0 Cu-0.6 Mn-1.2 Fe alloys were studied. The results show that Si addition promotes the formation of Chinese script α-Fe, and suppresses the precipitation of Al_3（Fe Mn） and Al_6（Fe Mn）. For the alloys produced without pressure, Si addition increases the volume fraction of porosity, resulting in remarkable decrease in ultimate tensile strength（UTS） and yield strength（YS）. For the alloys produced with 75 MPa pressure, Si addition improves UTS and YS owing to the formation of high number density of Al_2 Cu（θ） phases. The tensile properties of alloys increase with increasing applied pressure at the same Si content level, which is attributed to elimination of porosity, grain refinement strengthening and solid-solution strengthening. The alloy with 1.1% Si addition and 75 MPa pressure shows the best tensile properties, where the UTS, YS and elongation are 237 MPa, 140 MPa and 9.8%, respectively.展开更多
In the present work,samples of Al-Si-Cu piston alloy after T6 heat treatment were exposed for 2 h at temperatures ranging from 400 to 550°C.The evolution of surface roughness and microstructure of the alloy durin...In the present work,samples of Al-Si-Cu piston alloy after T6 heat treatment were exposed for 2 h at temperatures ranging from 400 to 550°C.The evolution of surface roughness and microstructure of the alloy during thermal exposure was studied by combination methods of roughness profiles,optical and scanning electron microscopy as well as XRD analysis.It is found that the roughness and mass of the alloy increase with the raise of the thermal exposure temperature,and the increasing rates of them are slow as the exposure temperature is below 500°C,but accelerates abruptly when the temperature is higher than 500°C.The variation of surface roughness of the alloy is closely related to phase transformation and oxidation during the thermal exposure.展开更多
基金Project(51374110)supported by the National Natural Science Foundation of ChinaProject(2015B090926004)supported by Science and Technology Program of Guangdong Province,ChinaProject(2015A030312003)supported by the Natural Science Foundation of Guangdong Province,China
文摘The effects of Si addition and applied pressure on the microstructure and tensile properties of as-cast Al-5.0 Cu-0.6 Mn-1.2 Fe alloys were studied. The results show that Si addition promotes the formation of Chinese script α-Fe, and suppresses the precipitation of Al_3（Fe Mn） and Al_6（Fe Mn）. For the alloys produced without pressure, Si addition increases the volume fraction of porosity, resulting in remarkable decrease in ultimate tensile strength（UTS） and yield strength（YS）. For the alloys produced with 75 MPa pressure, Si addition improves UTS and YS owing to the formation of high number density of Al_2 Cu（θ） phases. The tensile properties of alloys increase with increasing applied pressure at the same Si content level, which is attributed to elimination of porosity, grain refinement strengthening and solid-solution strengthening. The alloy with 1.1% Si addition and 75 MPa pressure shows the best tensile properties, where the UTS, YS and elongation are 237 MPa, 140 MPa and 9.8%, respectively.
基金Project(DLBF2018-KY-JS-066-J)supported by China North Engine Research InstituteProject(XAGDXJJ17008)supported by the Principal Fund of Xi’an Technological University,ChinaProjects(19JK0400,19JK0402)supported by the Education Fund of Shaanxi Province,China。
文摘In the present work,samples of Al-Si-Cu piston alloy after T6 heat treatment were exposed for 2 h at temperatures ranging from 400 to 550°C.The evolution of surface roughness and microstructure of the alloy during thermal exposure was studied by combination methods of roughness profiles,optical and scanning electron microscopy as well as XRD analysis.It is found that the roughness and mass of the alloy increase with the raise of the thermal exposure temperature,and the increasing rates of them are slow as the exposure temperature is below 500°C,but accelerates abruptly when the temperature is higher than 500°C.The variation of surface roughness of the alloy is closely related to phase transformation and oxidation during the thermal exposure.
