含锂2024铝合金组织及电学性能研究

发布时间：2018-10-29 12:47

【摘要】：近些年,随着我国公共基础产业的蓬勃发展,在国民生活中,电缆及其导线成为国民生活基础设施。铝合金线缆应用日益广泛,但我国铝合金缆线品种相对少,难以满足现代电力更加苛刻的要求。本论文通过某线缆厂实践现状发现高强度铝合金导线在生产过程中存在跳线、表面擦伤、单线断裂缺股、过扭、铝杆杂质导致的单丝表面三角口等问题,拟采用向2024铝合金添加不同含量锂元素,通过实验室对少量的铝合金组织及电学性能研究,通过电阻炉熔炼、制样,使用金相显微镜、SEM、拉伸压力试验机、显微硬度计、霍尔测试系统等仪器测试其组织及电学性能。通过对不同锂含量对2024铝合金组织及电学性能的研究发现,随着锂元素的添加,生成的Al_2CuLi相对合金硬度起到增强效果,经过均匀化处理后,亚稳定相Al_2CuLi相变为Al_2Cu相,分散在晶界处,LaCl和NaHB6反应生成LaB6,起到细化晶粒的作用;通过对其拉伸性能的测试,锂元素的添加对合金的抗拉强度起到了促进作用,观察试样拉伸断口扫描电镜照片发现均为滑移开裂和沿晶断裂的混合型断裂,断口处韧窝较深,延伸性较好;通过对其硬度的测试,锂元素的添加提高合金硬度有提高作用;通过对其电学性能的测试,锂元素的添加量为1.1%时,合金的导电性能优良。通过锂元素的添加,可以提高合金的机械性能,保证一定的导电性能,起到对线缆厂使用高强度合金铸棒的性能改善作用,对新疆地区高强度铝合金输变电产业的发展具有促进意义。
[Abstract]:In recent years, with the rapid development of China's public basic industry, cables and wires have become the infrastructure of national life in the national life. Aluminum alloy cable is widely used, but the variety of aluminum alloy cable in China is relatively few, so it is difficult to meet the more demanding requirements of modern power. In this paper, through the practice of a cable factory, it is found that there are some problems in the production process of high strength aluminum alloy wire, such as jumper wire, surface scratch, single wire fracture and lack of strands, torsion, triangulation of single wire surface caused by aluminum rod impurity, and so on. By adding different lithium elements to 2024 aluminum alloy, the microstructure and electrical properties of a small amount of aluminum alloy were studied in laboratory. The microstructure and electrical properties of 2024 aluminum alloy were studied by means of electric resistance furnace melting, sample preparation, metallographic microscope, SEM, tensile pressure tester and microhardness tester. Hall test system and other instruments to test its structure and electrical properties. Through the study of the microstructure and electrical properties of 2024 aluminum alloy with different lithium content, it is found that with the addition of lithium, the Al_2CuLi can enhance the hardness of the alloy and be homogenized. The metastable Al_2CuLi phase is transformed into Al_2Cu phase and dispersed at grain boundaries. The reaction of LaCl and NaHB6 produces LaB6, to refine the grain. The tensile strength of the alloy was promoted by the addition of lithium element. The SEM photos of the tensile fracture of the alloy showed that the tensile fracture was mixed mode fracture with slip crack and intergranular fracture, and the dimple at the fracture surface was deep. Good extensibility; By testing the hardness of the alloy, the addition of lithium element can improve the hardness of the alloy, and the electrical properties of the alloy can be improved by testing the electrical properties of the alloy, and the electrical conductivity of the alloy is excellent when the addition of lithium element is 1.1. Through the addition of lithium element, the mechanical properties of the alloy can be improved, and the electrical conductivity can be guaranteed, which can improve the performance of the wire cable factory using high strength alloy casting rod. It will promote the development of high-strength aluminum alloy power transmission and transformation industry in Xinjiang.
【学位授予单位】：昌吉学院
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TG146.21

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