大厚度钨基合金正挤压棒坯的溶剂脱脂特性.pdf

第21卷第2期
中国有色金属学报
2011年2月
Vol 21 No. 2
The Chinese Journal of Nonferrous Metals
Feb.2011
文章编号;1004-0609(2011)02-0364-07
大厚度钨基合金正挤压棒坯的溶剂脱脂特性
刘文胜,蔡青山,马运柱
(中南大学粉末治金国家重点实验室,长沙410083)
摘要:为了实现厚度达15mm钨基合金正挤压棒坯的无缺陷脱脂,对大厚度正挤压棒坯的溶剂脱脂行为和机理
以及大厚度棒坯溶剂脱脂过程的优化方法和效果进行研究。结果表明:大厚度棒坯的溶剂脱脂对温度非常敏感,
极易产生脱脂缺陷;棒坯厚度增大,粘结剂脱除速率降低,产生缺陷的几率增大,d12mm和d15m棒坯的适
宜溶剂脱脂工艺为(30℃,12b);415mm棒坯在30℃下脱脂6h,脱脂量不足30%,且随着脱脂时间的进一步延
长,脱脂速率显著下降;大厚度棒坯的溶剂脱脂受扩散控制,棒坯越厚,扩散路径越长,棒坯脱脂速率越小;采
用短周期多次浸溶剂方法来优化脱脂过程,实现了正挤压棒坯的无缺陷脱脂,且d12mn和d15mm棒坯的脱脂
量分别可高达55%和45%以上。
关键词:钨基合金;正挤压棒坯;溶剂脱脂;脱脂特性
中图分类号:TF124
文献标志码:
Solvent debinding characteristics for forward extrusion parts of
tungsten heavy alloy
LU Wen-sheng, CAI Qing-shan, MA Yun-zhu
State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China)
Abstract: In order to succeed in debinding thick parts of tungsten heavy alloy with thickness about 15 mm, the solvent
debinding process and mechanism of big size forward extrusion parts were studied. The optimization methods of sample
olvent debinding process and their effects were discussed. The results show that solvent debinding process of thick parts
is sensitive to solvent debinding temperature and is easy to generate debinding defects. With the increase of the thickness
of samples, the binder debinding ratio decreases, the formation probability of debinding defects rises under the optimum
solvent debinding condition of(30 12 h). The binder removal of d15 mm bar is less than 30% at 30C for 12 h, and
the debinding rate decreases significantly with further increasing debinding time. The solvent debinding process of thick
parts is a diffusion controlled process, the larger the thickness of samples is, the longer the diffusion path and the lowder
the debinding rate are. Taking a short cycle times immersing solvent method to optimize the debinding process, th
debound parts have no defect, and the debinding efficiency levels of d12 mm and d15 mm reach up 55%and 45%
Key words: tungsten heavy alloy; forward extrusion parts; solvent debinding; debinding characteristics
钨基合金具有优异的物理和力学性能,在军工领 extrusion molding,PEM)是制取管、棒、条和其他异
域中(如穿甲弹)广泛应用。随着科技的飞速发展,对型制品最有效的一种新型成形技术4?。在PEM工艺
大长径比动能杆式穿甲弹弹芯材料的制备和性能提中,脱脂是很重要的步骤,它是整个工艺步骤中限制
出更高的要求!。而粉末挤压成形技术( Powder挤压件向大尺寸、大厚度发展的关键步骤,直接影响
基金项目:国家自然科学基金资助项目(5074098)
收稿日期:2010-03-03;修订日期:2010-08-26
通信作者:马运柱,副教授:博士,电话:0731-88825;E-mai:zhuzipm(@mail.csu.edu.cn