固/液复合“半固态显微组织/枝晶组织”界面的组织与性能  

Microstructure and Properties of“Semi-solid Microstructure/Dendritic Microstructure”Interface by Solid-liquid Compound Casting

作　　者：郑小平 姜龙 李春晓 李红斌 田亚强 陈连生 ZHENG Xiaoping;JIANG Long;LI Chunxiao;LI Hongbin;TIAN Yaqiang;CHEN Liansheng(Key Laboratory of Ministry of Education for Modern Metallurgy Technology,North China University of Science and Technology,Tangshan 063210,China)

机构地区：[1]华北理工大学教育部现代冶金技术重点实验室,河北唐山063210

出　　处：《材料科学与工程学报》2020年第4期585-589,共5页Journal of Materials Science and Engineering

基　　金：国家自然科学基金资助项目(51474091,51574107);河北省自然科学基金资助项目(E2017209121);河北省高等学校科学技术研究资助项目(ZD2018242)。

摘　　要：采用固/液复合铸造法制备了界面组织特征为“半固态组织/枝晶组织”的7075/6061双金属复合材料,研究了不同半固态坯料预热温度与外熔体温度对界面组织形貌的影响,并检测了复合铸锭横截面的硬度分布。研究结果表明:随着坯料预热温度、外熔体温度的升高,半固态显微组织的固相颗粒会发生Ostwald熟化,向柱状晶组织形态转变;当坯料预热温度为300℃、外熔体温度为760℃、保温40 min、空冷凝固时,可获得较为理想的“半固态组织/枝晶组织”界面形态,且界面处的硬度呈缓和的梯度分布,达到了较好的冶金结合。7075/6061 composite materials with the“semi-solid microstructure/dendritic microstructure”interface were prepared by the solid-liquid compound casting.Effects of preheating temperature of the semi-solid billets and temperature of the external melts on interface morphology were analyzed.And hardness distributions on the cross section of the composite ingots were measured.While the preheating temperature and the external melt temperature are increasing,the Ostwald ripening of the semi-solid spherical particles occurs,and the semi-solid spherical particles change to the columnar grain.When the process parameters are preheating temperature of 300℃,external melt temperature of 760℃,holding time of 40min and air cooling,the“semi-solid microstructure/dendritic microstructure”interface is the best,the hardness of the interface is distributed with a slow gradient;the interface has a good metallurgical bond.

关 键 词：固/液复合铸造 半固态组织/枝晶组织 界面组织 硬度分布 

分 类 号：TB331[一般工业技术—材料科学与工程]