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过共晶al-mg2si合金材料研究进展

吉林化工学院学报 2020年第11期37卷 24-27,32页

作者：杜阳索忠源路大勇吉林化工学院材料科学与工程学院吉林吉林132022 吉林化工学院机电工程学院吉林吉林132022

mg2si颗粒具有熔点高、硬度高、密度低和热膨胀系数小等特点,其作为增强体与铝基体结合性能良好,使得al-mg2si合金材料拥有良好的力学性能.过共晶al-mg2si合金材料在拥有低密度特点的同时具备了优异的耐磨性能,成为了汽车、摩托车发动... 详细信息

mg2si颗粒具有熔点高、硬度高、密度低和热膨胀系数小等特点,其作为增强体与铝基体结合性能良好,使得al-mg2si合金材料拥有良好的力学性能.过共晶al-mg2si合金材料在拥有低密度特点的同时具备了优异的耐磨性能,成为了汽车、摩托车发动机活塞和气缸盖生产的可选材料.介绍了al-mg2si合金材料的发展现状,重点综述了过共晶al-mg2si合金材料的制备技术、变质机制和合金元素的变质作用.

关键词：铝合金 al-mg2si 过共晶研究进展

Effect of reinforcement amount, mold temperature, superheat, and mold thickness on fluidity of in-situ al-mg_2si composites

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China Foundry 2018年第1期15卷 66-74页

作者： Reza Vatankhah Barenji Department of lndustrial Engineering Hacettepe University Beytepe Campus Ankara 06800 Turkey

In the present study, the effects of mold temperature, superheat, mold thickness, and mg_2si amount on the fluidity of the al-mg_2si as-cast in-situ composites were investigated using the mathematical models. Composites with different amounts of mg_2si were fabricated, and the fluidity and microstructure of each were then analyzed. For this purpose, the experiments were designed using a central composite rotatable design, and the relationship between parameters and fluidity were developed using the response surface method. In addition, optical and scanning electron microscopes were used for microstructural observation. The ANOVA shows that the mathematical models can predict the fluidity accurately. The results show that by increasing the mold temperature from 25℃ to 200℃, superheat from 50℃ to 250℃, and thickness from 3 mm to 12 mm, the fluidity of the composites decreases, where the mold thickness is more effective than other factors. In addition, the higher amounts of mg_2si in the range from 15 wt.% to 25 wt.% lead to the lower fluidity of the composites. For example, when the mold temperature, superheat, and thickness are respectively 100℃, 150℃, and 7 mm, the fluidity length is changed in the range of 11.9 cm to 15.3 cm. By increasing the amount of mg_2si, the morphology of the primary mg_2si becomes irregular and the size of primary mg_2si is increased. Moreover, the change of solidification mode from skin to pasty mode is the most noticeable microstructural effect on the fluidity.

关键词： al-mg2si composites microstructure fluidity

al-mg_2si共晶合金在“神舟2号”飞船上定向复合生长

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中国科学（A辑） 2002年第8期32卷 725-729页

作者：潘明祥李顺朴赵德乾汪卫华闻平俞育德聂玉昕赵生旭庄艳歆陈熙琛中国科学院物理研究所极端条件物理重点实验室及凝聚态物理中心北京100080

在我国“神舟2号”飞船上进行的al-mg2si在共晶合金的定向生长样品的初步分析结果.分析表明微重力对al-mg2si共晶合金的定向生长有影响.空间凝固样品中的共晶团比地面的粗大,定向生长效果比地面样品的差,但片层厚度没有显示出明显差异,... 详细信息

在我国“神舟2号”飞船上进行的al-mg2si在共晶合金的定向生长样品的初步分析结果.分析表明微重力对al-mg2si共晶合金的定向生长有影响.空间凝固样品中的共晶团比地面的粗大,定向生长效果比地面样品的差,但片层厚度没有显示出明显差异,而空间样品中平均片层间距比地面样品中的小.并就空间环境对al-mg2si共晶合金的定向生长的影响进行了讨论.

关键词： al-mg2si 共晶合金 “神舟2号”飞船定向复合生长微重力内生复合材料铝硅化镁微观结构

Effect of Fe-impurity on tribological properties of al-15mg_2si composite

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Transactions of Nonferrous Metals Society of China 2018年第6期28卷 1084-1093页

作者： A.NADIM R.TAGHIABADI A.RAZAGHIAN M.T.NOGHANI M.H.GHONCHEH Department of Materials Science and Ceramic Engineering Imam Khomeini International UniversityQazvinIran School of Metallurgy and Materials Engineering Iran University of Science and TechnologyTehranIran

The effect of Fe-impurity（0.2%-2%, mass fraction） on the microstructure, dry sliding wear, and friction properties of al-15 mg2 si composite was investigated using a pin-on-disk tester under the applied pressures of 0.25, 0.5 and 1 MPa at a constant sliding speed of 0.13 m/s. According to the results, Fe modified the primary mg2 si particles from irregular dendritic form to smaller particles with polyhedral shapes, refined the pseudo-eutectic structure, and led to the formation of hard b-al5 Fe si platelets in the matrix. In spite of hardness improvement by these microstructural changes, the resistance of the composite against dry sliding wear was impaired. SEM examination of the worn surfaces, wear debris, and subsurface regions confirmed the negative effect of b-phase on the tribological properties. It was found that b-particles were fractured easily, thereby decreasing the potential of the substrate to resist against sliding stresses and giving rise to the instability and easy detachment of tribolayer as large delaminated debris. The friction results also revealed that Fe slightly decreased the average friction coefficient, but increased the fluctuation in friction.

关键词： al-mg2si in-situ composite tribology sliding wear friction