脉冲磁场-机械振动复合处理对H62黄铜凝固组织和硬度的影响.pdf

造
May 2014
424
FOUNDRY
fol. 63 No5
脉冲磁场一机械振动复合处理对H62黄铜凝固
组织和硬度的影响
谢小华,周全,陈乐平,肖程波2,汤鑫2
(1.南昌航空大学航空制造工程学院,江西南昌330063;
2.北京航空材料研究院先进高温結衲材料重点实验室,北京100095
摘要:对比研究了未处理、脉冲磁场处理、机械振动处理和脉冲磁场-机械振动复合处理条件下H62黄锎的凝固组织
的变化,并考察了复合处理条件下磁场参数和冷却条件对合金凝固组织和硬度的影响。结果表明:经脉冲磁场-机械
振动复合处理后,初生@相由粗大、发达的树枝晶变成短小的棒状枝晶,昌细化效果好于单一的脉冲磁场或机械振
动处理;随着脉冲电压或烦率的增加,初生@相逐渐退化,且硬度随之提高;随着浇注温度或铸型温度的增加,复
合处理后,初生相不断细化,便度逐渐提高,但当铸型温度达到1000℃时,初生@相有所粗化,硬度下降。
关键词:脉冲磁场;机械振动;凝固组织;硬度
中图分类号:TG292文献标识码:A文章编号:1001-4977(2014)05-0424-05
Effect of Compound Treatment of Pulsed Magnetic Field and
Mechanical Vibration on Solidification Structure and
Hardness of H62 Brass
XIE Xiao-hua, ZHOU Quan CHEN Le-ping, XIAO Cheng-bo, TANG Xin'
(1. School of Aeronautical Manufacturing Engineering, Nanchang Hangkong University, Nanchang 330063, Jiangxi, China,
2. Science and Technology on Advanced High Temperature Structure Materials Laboratory, Beijing Institute of Aeronautical
Material, Beiiing 100095, China
Abstract: Solidification structure of H62 brass without treatment, with pulsed magnetic field treatment
mechanical vibration treatment and compound treatment of pulsed magnetic field and mechanical vibration
were studied comparatively. The influences of parameters of magnetic field and cooling condition on
solidification structure and hardness of the alloy with compound treatment were investigated. The experimental
results show that solidification structure of H62 brass can be refined greatly by compound treatment during the
course of solidification. Primary a phase is changed from coarse and well-developed dendrites to short and
rod-shaped dendrites, which is more efficient than the refinin effect of pulsed magnetic field or mechanical
vibration treatment. With the increase of the pulse voltage or frequency, primary a phase degrades and hardness
increases. Primary a phase refines gradually with the increase of pouring temperature or mold temperature wit.
compound treatment. However, primary a phase is coarsened and hardness decreases when the mold
temperature reaches to 1 000 C
Key words: pulsed magnctic field; mechanical vibration solidification structure; hardnes
H62黄铜具有很高的强度,良好的力学性能和加境友好、对金属熔体无污染和易于处理,因而具有重
工性能,抗腐蚀性强,在仪器仪表、卫生洁具、水暖要的研究价值和实用价值。目前,机械振动、电磁场
器材、液压阀门等方面得到广泛应用,素有“商业黄和超声波等都已独立用于细化合金组织,而将外场进
铜”之称。但黄铜在一般铸造过程中易出现晶粒粗大行复合处理合金凝固组织的研究报道较少。付浩四等研
和柱状晶比例大的问题,导致材料性能下降,在后续究了超声-机械振动复合处理对A791D-3Ca镁合金凝固
的热加工过程中易出现“热裂”现象叫。通过细化晶粒组织的影响,发现复合处理可以显著细化合金的初生
能够有效控制和改善黄铜的组织以及提高其力学性能。相,其细化效果好于单一的机械振动或超声处理。李
外场处理(如机械振动,电磁场和超声波等)因其环捷竽研究发现功率超声场和旋转电磁场复合处理可以
基金项目:国家自然科学基金项目(51261026);航空科学基金项目(20125356009)。
收稿日期:2013-11-29收到初稿,2014-01-14收到修订稿。
作者简介:谢小华(1989-),男,硕士生,主要从事电磁振动在材料中的应用研究。E-mail:wymxxh2012c163.com