Mn元素对过流冷却过共晶Al-22Si-2Fe-xMn合金显微组织及耐磨性的影响

发布时间：2018-06-06 08:43

本文选题：铝硅铁合金 + 过流冷却　；参考：《工程科学学报》2017年02期

【摘要】：采用常规铸造和分段式倾斜板过流冷却铸造工艺制备Al-22Si-2Fe-xMn合金,研究表明:过流冷却制备工艺能够改善初生Si形貌及尺寸,但对针状富Fe相作用有限.利用扫描电镜、X射线衍射及透射电镜等手段分析过流冷却条件下Mn元素添加对富Fe相晶体结构的影响,通过摩擦磨损实验研究不同Mn/Fe质量比的过共晶Al-Si合金的硬度及耐磨损性能.结果表明:随着过流冷却铸造过共晶Al-Si合金中Mn/Fe质量比增加,合金中四方结构的长针状富Fe相逐渐减少直至基本消失,当Mn/Fe质量比为0.7时,富Fe相主要为六方结构的块状或鱼骨状α-Al_(15)(Fe,Mn)_3Si_2相,此时,合金耐磨性较未添加Mn元素时有所提升,磨损机制以磨料磨损方式为主.
[Abstract]:Al-22Si-2Fe-xMn alloy was prepared by conventional casting and segmented inclined plate overcurrent cooling casting. The results showed that the superflow cooling process could improve the morphology and size of primary Si, but had limited effect on the needle-rich Fe phase. The effect of mn addition on the crystal structure of Fe-rich phase was analyzed by means of scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The hardness and wear resistance of hypereutectic Al-Si alloy with different Mn/Fe mass ratio were studied by friction and wear test. The results show that with the increase of Mn/Fe mass ratio in hypereutectic Al-Si alloy cast by overcurrent cooling, the long needle-rich Fe phase of tetragonal structure in the alloy decreases gradually until it disappears, and when the mass ratio of Mn/Fe is 0.7, The Fe-rich phase is mainly a hexagonal or fishbone type 伪 -Al _ (1) C _ (15) / Fe _ (mn) _ 3Si _ (2) phase. At this time, the wear resistance of the alloy is improved compared with that of the alloy without mn addition, and the wear mechanism is mainly abrasive wear mode.
【作者单位】：昆明理工大学材料科学与工程学院;金属先进凝固成形及装备技术国家地方联合工程实验室;昆明理工大学分析测试研究中心;
【基金】：国家自然科学基金资助项目(51505205,51261011) 昆明理工大学自然科学研究基金资助项目(20159X9) 云南省教育厅科学研究基金资助项目(2015Y058) 昆明理工大学学生课外学术科技创新基金资助项目(2015YB011)
【分类号】：TG292

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