含铋铝基轴承材料摩擦磨损性能研究

发布时间：2018-05-20 17:29

  本文选题：铋 + 2A12铝合金　； 参考：《合肥工业大学》2017年硕士论文

【摘要】：铝基滑动轴承合金是一种质量轻、比强度高、导热性好的轴承材料,具有良好耐腐蚀和减摩耐磨性能,在机械、汽车、航空航天等领域中有广泛应用。铝锡合金材料质量轻且具有良好的减摩耐磨性、顺应性、嵌藏性和一定的抗咬合能力,正愈来愈多地代替传统的铜基和巴氏合金。为进一步发挥铝基轴承高比强度、良好摩擦学特性等优势,改善铝锡合金在承载能力及摩擦学性能方面的不足,本文在2A12基体中添加低熔点组元Bi,进一步研究了Bi添加量为0wt.%~8wt.%的2A12合金的力学及摩擦学性能;试验过程中发现Bi在铝基体中较易发生偏析,对于准确研究其对铝基轴承合金摩擦磨损性能的影响较为不利,为此对含Bi铝基轴承材料的制备工艺进行了一定的优化,探讨了工艺优化后含铋2A12合金的力学和摩擦磨损等性能,并将含Bi 2A12合金与含Sn合金进行对比。研究表明:铸造工艺的优化有利于Bi相均匀分布的均质合金的形成,熔炼温度为800℃,冷却方式采用100℃水冷,另外采用200r/min的机械方式搅拌效果较好。低熔点组元Bi的添加降低了材料的力学性能,但降低的程度明显低于锡对材料力学性能的影响;随着Bi含量的增加,铝基材料摩擦磨损状况得到明显改善,承载能力也相应提高,与相同含量的含锡材料相比,含Bi合金材料强度高、摩擦学性能好。低熔点组元铋与锡相似,在摩擦过程中软化熔化析出,降低接触区域的剪切强度,避免粘着撕裂的发生,起到较好的减摩抗粘着作用,而且由于球状分布的富Bi相对基体割裂作用较小,使基体合金保持较好的承载能力,从而使含Bi铝基轴承材料在逐级加载条件下综合表现较好。
[Abstract]:Al-base sliding bearing alloy is a kind of bearing material with light weight, high specific strength and good thermal conductivity. It has good corrosion resistance and friction-reducing wear resistance, and has been widely used in mechanical, automotive, aerospace and other fields. Aluminum-tin alloy materials with light weight, good friction and wear resistance, compliance, inclusiveness and certain bite resistance are more and more replacing the traditional copper base and Babbitt alloy. In order to give full play to the advantages of high specific strength and good tribological properties of Al-base bearings, and to improve the load-carrying capacity and tribological properties of Al-Sn alloy, In this paper, the mechanical and tribological properties of 2A12 alloy with Bi content of 0wt.% and 8wt.% have been further studied by adding low melting point component Bi into 2A12 matrix, and the segregation of Bi in aluminum matrix has been found during the experiment. In order to accurately study its influence on the friction and wear properties of Al-base bearing alloy, the preparation process of the bearing material containing Bi was optimized. The mechanical properties, friction and wear properties of bismuth containing 2A12 alloy were discussed, and the comparison between Bi 2A12 alloy and Sn containing alloy was carried out. The results show that the optimization of casting technology is advantageous to the formation of homogeneous alloy with homogeneous distribution of Bi phase. The melting temperature is 800 鈩，

本文编号：1915575