WANG Qian
,
WANG Jian
,
WENG Xiaojun
,
SUN Jian
,
CHEN Shipu
,
HU Gengxiang (Shanghai Jiaotong University
,
Shanghai 200010. China)
金属学报(英文版)
To explore the approaches of combined toughening and strengthening of the Al_3Ti-based L1_2 intermetallic alloys, multiphase Al_3Ti alloys formed by combining with reinforcement or by second phase precipitation are being studied. The interface reactions between Al_(66)Fe_9Ti_(25)matrix and SiC reinforcement were investigated. It is determined that SiC is chemically incompatible with the Al_(66)Fe_9Ti_(25)matrix, Al_2O_3 barrier coating on SiC by sol-gel process was developed to minimize the interfacial reactions. On the other hand, a new type of Al_3Ti-based alloy having a L1_2 matrix with second phase precipitation has been developed. The quaternary alloys based on Al_(66)Fe_9Ti_(25)and modified with Nb additions, consist of a L1_2 matrix and D0_(22) second phase in the annealed state ,but the second phase can be dissolved by solution treatment and precipitated during high temperature aging.
关键词:
:Al_3Ti alloy
,
null
,
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,
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,
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高振
,
杜晓东
,
蒋延涛
,
汪峰
,
周丹
,
沈健
,
刘光复
材料热处理学报
采用粉末埋入反应辅助涂覆技术处理后,SiC表面产生由TiC 、Ti5Si3、Ti8C5等组成Ti预涂覆层.通过等离子喷焊技术将经上述预涂覆的SiC颗粒与铁基合金熔覆于工件表面,制备SiC增强铁基合金复合涂层.结果表明:Ti涂覆SiC颗粒增强涂层内颗粒得到保留,受高温作用会发生一定分解,分解产物改变了基体的成分,进而影响基体的结晶模式和组织形态,出现了树枝晶和多边形块状碳化物.Ti涂覆SiC颗粒的颗粒增强作用以及分解产物的产生弥散强化和固溶强化作用,使得复合涂层的平均硬度高于纯铁基涂层,表面的维氏硬度值最高可达961 HV0.2,但SiC颗粒在基体中分布稀疏,颗粒增强效果不明显.
关键词:
预涂覆
,
显微组织
,
界面反应
,
显微硬度
