The homogenization on microstructure and mechanical properties of 2A50 aluminum alloy prepared by liquid forging was investigated.Wheel hubs were produced using direct and compound loading.The results show that the mi...The homogenization on microstructure and mechanical properties of 2A50 aluminum alloy prepared by liquid forging was investigated.Wheel hubs were produced using direct and compound loading.The results show that the microstructure and mechanical properties are inhomogeneous in direct forged samples.The microstructure of the wall is coarser than that of the base,and the mechanical properties are lower and some defects are detected at the wheel corner.Using compound loading,the microstructure and mechanical properties of the wall are improved evidently.With increasing feeding amount,the microstructure and mechanical properties become more homogeneous.The defects disappear when the feeding amount is 4 mm.The forged wheel hubs could obtain fine and homogeneous microstructure with grain size of 20-30 μm,tensile strength of 355 MPa and elongation of 10% when the feeding amount is 10 mm.The microstructure and mechanical properties of liquid forged workpieces could be controlled and homogenized using compound loading.展开更多
The corrosion behaviours of Mg-5Y-7Gd-1Nd-0.5Zr magnesium alloys prepared by as-casting and extrusion were investigated in 5% NaCl aqueous solution by immersion and electrochemical tests. The microstructure indicates ...The corrosion behaviours of Mg-5Y-7Gd-1Nd-0.5Zr magnesium alloys prepared by as-casting and extrusion were investigated in 5% NaCl aqueous solution by immersion and electrochemical tests. The microstructure indicates the mean grain size of 15 μm for the extruded and 100 μm for the as-cast Mg-5Y-7Gd-1Nd-0.5Zr magnesium alloys. The corrosion morphology of as-cast sample shows pitting corrosion and little filiform corrosion, but that of the extruded sample shows pitting corrosion at the initial stage. The corrosion rate of extruded sample is higher than that of as-cast Mg-5Y-7Gd-1Nd-0.5Zr alloy according to the immersion test. The second phases containing RE acting as cathodes improve the corrosion properties. The corrosion potentials of as-cast and extruded Mg-5Y-7Gd-1Nd-0.5Zr alloys are -1.658 V and -1.591 V, respectively. The origins of the distinctive corrosion behavior of as-cast and extruded Mg-5Y-7Gd-1Nd-0.5Zr Mg alloys were discussed.展开更多
采用添加Al Ti B和四元复合变质剂对ZL101合金熔体进行处理,研究浇铸产品的力学和耐腐蚀性能。结果表明,Al Ti B和四元复合变质剂不仅能够抑制ZL101合金枝晶的生成,同时也具有良好的晶粒细化作用,加入量为0.5%,保温30 min后,在720℃浇...采用添加Al Ti B和四元复合变质剂对ZL101合金熔体进行处理,研究浇铸产品的力学和耐腐蚀性能。结果表明,Al Ti B和四元复合变质剂不仅能够抑制ZL101合金枝晶的生成,同时也具有良好的晶粒细化作用,加入量为0.5%,保温30 min后,在720℃浇铸变速箱的晶粒由平均150μm减小至62μm,并使合金的强度和伸长率分别提高27%和42%,同时提高ZL101合金的耐蚀性。Al Ti B和四元复合变质剂并不能改变硅形貌,将硅由未变质时的针状生长为球状或块状是Na F的作用。展开更多
基金Projects (50774026, 50875059) supported by the National Natural Science Foundation of ChinaProject (20070420023) supported by the China Postdoctoral Science FoundationProject (2008AA03A239) supported by the National High-tech Research and Development Program of China
文摘The homogenization on microstructure and mechanical properties of 2A50 aluminum alloy prepared by liquid forging was investigated.Wheel hubs were produced using direct and compound loading.The results show that the microstructure and mechanical properties are inhomogeneous in direct forged samples.The microstructure of the wall is coarser than that of the base,and the mechanical properties are lower and some defects are detected at the wheel corner.Using compound loading,the microstructure and mechanical properties of the wall are improved evidently.With increasing feeding amount,the microstructure and mechanical properties become more homogeneous.The defects disappear when the feeding amount is 4 mm.The forged wheel hubs could obtain fine and homogeneous microstructure with grain size of 20-30 μm,tensile strength of 355 MPa and elongation of 10% when the feeding amount is 10 mm.The microstructure and mechanical properties of liquid forged workpieces could be controlled and homogenized using compound loading.
基金Project (2011BAE22B01) supported by the National Key Technology R&D Program of China
文摘The corrosion behaviours of Mg-5Y-7Gd-1Nd-0.5Zr magnesium alloys prepared by as-casting and extrusion were investigated in 5% NaCl aqueous solution by immersion and electrochemical tests. The microstructure indicates the mean grain size of 15 μm for the extruded and 100 μm for the as-cast Mg-5Y-7Gd-1Nd-0.5Zr magnesium alloys. The corrosion morphology of as-cast sample shows pitting corrosion and little filiform corrosion, but that of the extruded sample shows pitting corrosion at the initial stage. The corrosion rate of extruded sample is higher than that of as-cast Mg-5Y-7Gd-1Nd-0.5Zr alloy according to the immersion test. The second phases containing RE acting as cathodes improve the corrosion properties. The corrosion potentials of as-cast and extruded Mg-5Y-7Gd-1Nd-0.5Zr alloys are -1.658 V and -1.591 V, respectively. The origins of the distinctive corrosion behavior of as-cast and extruded Mg-5Y-7Gd-1Nd-0.5Zr Mg alloys were discussed.
文摘采用添加Al Ti B和四元复合变质剂对ZL101合金熔体进行处理,研究浇铸产品的力学和耐腐蚀性能。结果表明,Al Ti B和四元复合变质剂不仅能够抑制ZL101合金枝晶的生成,同时也具有良好的晶粒细化作用,加入量为0.5%,保温30 min后,在720℃浇铸变速箱的晶粒由平均150μm减小至62μm,并使合金的强度和伸长率分别提高27%和42%,同时提高ZL101合金的耐蚀性。Al Ti B和四元复合变质剂并不能改变硅形貌,将硅由未变质时的针状生长为球状或块状是Na F的作用。
