陶瓷晶须增强水溶性盐芯成形特征与使用性能.pdfVIP

维普资讯 学兔兔 铸 造 Mar．2008 · 234· FOUNDRY Vo1．57 No．3 陶瓷晶须增强水溶性盐芯成形特征与使用性能 万 里，徐鹏程，罗吉荣 (华中科技大学材料成形与模具技术国家重点实验室，湖北武汉430074) 摘要：以某些内腔结构复杂、质量要求高，用传统型芯难以满足的高压力成形 (如压铸、挤压铸造)的铸件为对象， 旨在开发出一种新的高强韧水溶性盐芯制造技术。试验研究了重力浇注条件下，以硼酸铝晶须为强化相的卤化物盐芯 的成形特征以及凝固组织、水溶性、抗吸湿性和力学性能的变化。结果表明，所有浇注成形的盐芯试样表面都起皱， 但晶须的加入可减少表面折皱，有利于改善盐芯表面质量。随晶须加入量增加，复合盐芯晶粒细化，凝固收缩率也随 之降低；当硼酸铝晶须的添加量为2．5％和4．5％时，NaC1和KCI盐芯的体收缩率分别达到最低约为8．1％和9．0％。晶须加 入可显著改善复合盐芯抗吸湿性，却延长了盐芯的溃散即水溶时间。复合盐芯的抗弯强度随硼酸铝晶须加入量增加而 增大，在晶须含量分别为9％和7％时，KCI和NaC1复合盐芯的抗弯强度为16．50MPa和9．25 MPa，比纯盐芯强度提高约6 倍和3．7倍，但当晶须加入量过大时，会导致熔融盐粘性上升而难以浇注成形。 关键词：高压铸造；复合材料；盐芯；晶须 中图分类号：TG249．2；TG132 文献标识码：A 文章编号：1001—4977(2008)03—0234—05 Properties and FOrming Characters of Water Soluble Salt-Core Reinforced by Ceramic Whiskers WAN Li，XU Peng—cheng，LUO Ji—rong (State Key Laboratory of Materials Processing and Die＆Mold Technology。Huazhong University of Science and Technology，Wuhan 430074，Hubei，China) ’ Abstract：Development of a new technology on high strength and toughness water soluble salt—core iS required for manufacturing some high—quality and complicated castings by high—pressure die casting．1n this study．the salt core composites reinforced by aluminum borate whisker were produced by gravity casting．The forming characters，macrostructure，water—solubility，anti—moisture absorption and mechanical properties of salt core were investigated．As a result．it was found there were SUrface foIds on all these specimens．but which can be decreased by whiske