毕业设计（论文）-热处理对铝硅合金电导率的影响.doc

密级:



热处理对铝硅合金电导率的影响
The impact of heat treatment on the conductivity of Al-Si alloy
学院:材料学院
专业班级:材料成型及控制工程0805班
学号:080201143
学生姓名:李振庄
指导教师:白彦华(教授)
年月
摘要
Al-Si系合金一般含 Si 量为4~10%,合金的组织由韧性的α固溶体和坚硬的共晶硅相所构成,具有良好的耐磨性以及一定的强度和韧性。由于硅的线膨胀系数小(仅为铝的1/6 左右),所以Al-Si合金也具有较小的线膨胀系数,常用于制造高速运动中经受摩擦的机器零件,以及要求在工作温度变化条件下能保持较高尺寸精度的零件。Al-Si合金的铸造性能良好,且不形成热裂,因而可用来铸造各种形状复杂的铝合金铸件。但是,目前铸态Al-Si合金的电导率尚不尽人意,在输电过程中,会造成社会资源的巨大浪费,甚至还会引起机械设备的事故,严重降低输电率。因此,研究Al-Si合金的电导率对国家的国民经济发展有着重大的现实益义。
本实验根据新东北电气沈阳高压开关有限公司对ZL101A合金电导率的要求,对铝硅合金进行了不同的固溶处理和时效处理,研究热处理对Al-Si合金电导率的影响,在保证合金具有一定的硬度的前提下,来提高合金的电导率。
实验结果表明:铸态Al-Si合金的电导率约为37 %IACS左右,而通过热处理之后的Al-Si合金的电导率很多都能打到40 %IACS以上,甚至更高,提高了8%以上。但是,通过对其硬度的测试,发现电导率越高,硬度值越低,所以只通过热处理,电导率和硬度二者是不能兼得的。
关键词:Al-Si合金;热处理;电导率;硬度
Abstract
The content of Si in Al-Si alloys generally is 4%~10%, and the alloy is made up of f α-solid solution and the hard eutectic silicon phase , with good wear resistance ,strength and toughness. Because the linear expansion coefficient of silicon is small (only about 1/6 of the aluminum), the Al-Si alloy has a smaller linear expansion coefficient, commonly used in the manufacture of high-speed movement of machine parts subjected to friction, and require to maintain the high dimensional accuracy of parts under the changing in operating temperature conditions. Al-Si alloy casting has good performance, without the formation of thermal cracking, which can be used to plex aluminum castings of various shapes. However, the conductivity of the cast of Al-Si alloy is still unsatisfactory, It will cause a huge waste of social resources, machinery and equipment or even cause an accident, severely reducing the transmission rate in the transmission process. Therefore, the study of Al-Si alloy conductivity has great practical benefits righteousness to the country's national economic development.
According to the requirements of ZL101A alloy of the Shenyang High Voltage Switchgear Co., Ltd. New Northeast Electric conductivity of, , This experimen