型内感应加热铝-钢双金属复合界面的研究

Study of Transition Layer of Aluminum-steel Bimetal Compound Produced by Induction Heating in Mold

双金属复合铸件外圈采用铸造铝合金,内圈选取碳素结构钢,采用型内感应加热工艺进行复合。造型时内层钢套预先放置在砂型中,复合时将包含有钢套的砂型整体放入到感应圈内采用中频感应原理对钢套进行预热,达到预定温度后浇注并继续进行加热,复合层将基体钢套包覆后停止加热。所得到的双金属复合铸件结合界面为完全冶金结合,复合层组织为连续分布FeAl_3与Fe_2Al_5中间化合物,界面结合强度为76.4MPa。

Selecting cast aluminum alloy and cast steel as inner loop and outer loop of the bimetal compound casting respectively, the casting was produced by induction heating in mold. Inner steel bush was pre-positioned in sand mold when moulding. The sand mold with steel bush was whole put in induction coil when preheating. After being up to the predetermined temperature, molten aluminum was poured and heated coutinuously, then to stop heating after molten aluminum liquid cladding the steel bush. The detecting results show that,the interface of bimetal compound casting is completely metallurgical combine,there are two continuous distribution layers （FeAl3 and Fe2Al5） in the interface. The bonding strength is about 76.4MPa.