组织性能的影响
( 1. 大连理工大学 铸造工程研究中心， 大连 116023；
2. 河南金龙股份有限公司，新乡 453000)
摘 要: 研究了工频电磁场对水平连铸紫铜管坯表面质量、力学性能和组织的影响。结果表明：在工频电磁场作用下，紫铜管坯的表面质量得到了一定的改善，励磁电流为140 A时，表面粗糙度由120 μm降到90 μm；施加电磁场后，柱状晶得到了显著的细化，并在管坯内侧得到了细小的等轴晶组织；随着电流强度的增加，等轴晶区扩大，晶粒在周向上分布更加均匀；施加电磁场后，管坯的力学性能随着励磁电流的增加得到了显著的提高，当励磁电流为140 A时，抗拉强度提高了15%，延伸率提高了10%，管坯硬度提高了11%。
关键字: 电磁场；水平连铸；铜管坯
surface quality, macrostructure and
property of horizontal continuous casting
of copper hollow billet
（ 1. Research Center of Foundry Engineering,
Dalian University of Science and Technology，Dalian 116023，China;
2. Henan Golden Dragon Precise Copper Tube Incorporation,
Xinxiang 453000, China）
Abstract: The influence of commercial frequency electromagnetic field on the surface quality, mechanical properties and macrostructure of copper hollow billet prepared by horizontal continuous casting method was investigated. The results indicate that high quality copper hollow billet can be obtained by the application of electromagnetic field during horizontal continuous casting. When the imposed current is 140 A, surface roughness decreases from 120 μm to 90 μm. Columnar grains are evidently refined and fine equiaxed grains are acquired in the inner side of cross-section. With the increase of input current, equiaxed grains zone widens and grains distribute more uniform in the circumferential direction. Moreover, the mechanical properties are all remarkably enhanced with the increase of electromagnetic intensity. When the input current is 140 A, the increases of tensile strength, elongation and hardness are 15%, 10% and 11%, respectively.
Key words: electromagnetic field; horizontal continuous casting; copper hollow billet
