TiC_p/7075 Al基复合材料二次加热中晶粒长大规律  

Grain growth law of TiC_p/7075 Al composites during reheating

作　　者：张复懿[1] 刘慧敏[1,2] 刘丽[1] 

机构地区：[1]内蒙古工业大学材料科学与工程学院,内蒙古呼和浩特010051 [2]内蒙古新材料工程技术中心,内蒙古呼和浩特010051

出　　处：《材料热处理学报》2010年第6期23-27,共5页Transactions of Materials and Heat Treatment

基　　金：国家自然科学基金资助项目(50661003)

摘　　要：采用原位反应近液相线铸造法制备4.4%TiCp/7075Al基复合材料,在600℃保温10～60 min,水淬固定其半固态组织,研究半固态二次加热过程中合金的晶粒长大规律,并与采用同样方法制备的7075基体合金进行对比分析。结果表明,4.4%TiCp/7075Al基复合材料的晶粒粗化速率常数为118.96μm3/s,远小于7075基体合金的晶粒粗化速率常数311.7μm3/s,晶粒长大速率明显减慢。分析其原因,由于原位TiC颗粒的生成,使得4.4%TiCp/7075Al基复合材料的晶粒长大激活能增加约50%,从而对二次加热过程中晶粒迅速长大的行为起到了显著的抑制作用。4.4% TiCp /7075 Al composite was prepared by in-situ reactive near-liquidus casting,and 7075 Al alloy and the composite were re-heated isothermally at 600 ℃,which is in the two-phase（liquid and solid） region（477—635 ℃） of near-liquidus casting 7075 alloy,for 10—60 min,then quenched in water.The effect of in-situ TiC particles on microstructure of the 4.4% TiCp /7075 Al composite was examined and it was compared with that of the 7075 alloy.The result shows that the coarsening velocity constant of grain for 4.4% TiCp /7075 Al composite is 118.96 μm3 /s,which is more less than 311.7 μm3 / s of 7075 alloy.The activation energy of grain growth for the in-situ 4.4% TiCp /7075 Al composite is about 1.5 times of that for the 7075 alloy,which is responsible for the inhibition of grain growth of 4.4% TiCp /7075 Al composite.

关 键 词：TiCp/7075 AL基复合材料 原位反应近液相线铸造 半固态 二次加热 晶粒长大 

分 类 号：TB331[一般工业技术—材料科学与工程]