Controlled casting of Al-Si hypereutectic alloys
    3.
    发明授权
    Controlled casting of Al-Si hypereutectic alloys 失效
    Al-Si过共晶合金的控制铸造

    公开(公告)号:US5316070A

    公开(公告)日:1994-05-31

    申请号:US867113

    申请日:1992-07-02

    摘要: Al base - Si hypereutetic alloys can exhibit problems of variable and unwanted microstructure throughout the section of the article being cast. This problem is overcome by controlled cooling of the mold in critical areas, to remove or prevent excessive accumulation of heat energy and avoid the formation of intense convection currents in still molten alloy. Consequently, the necessary coupled growth of the Al-Si eutectic is promoted and the resultant microstructure is substantially free of primary Si. The 3HA and modified 3HA alloys of the applicant are considered on the basis of their wear resistance and improved machineability for automotive applications, such as engine blocks and cylinder heads. A first feature of the controlled cooling procedure is supply of coolant to regions in the mold, above and extending from the gate, such that solidification progresses uniformly from the remote regions of the mold spaces towards the gate to give a substantially uniform microstructure throughout the casting. Various coolants may be used, so that temperature in the vicinity of the gate is 50.degree.-75.degree. C. above those at the extremities. A second feature of the controlled cooling procedure consists of supplying melt to the mold cavity through a plurality of gates, spaced relative to one another in the critical control region of the mold. The result of using such a plurality of gates, is that the energy accumulated is more widely distributed in a plurality of critical control regions, in order to achieve the necessary temperatures at the remote and gate regions and temperature differentials between these.

    摘要翻译: PCT No.PCT / AU90 / 00588 Sec。 371日期:1992年7月2日 102(e)日期1992年7月2日PCT 1990年12月11日PCT PCT。 出版物WO91 / 02100 日期1991年2月21日.Al基-SSi过度烧蚀合金可以在铸件的整个部分呈现出可变和不需要的微结构的问题。 这个问题通过在关键区域中模具的受控冷却来克服,以去除或防止热能的过度积累,并避免在仍然熔融的合金中形成强烈的对流。 因此,促进Al-Si共晶的必要的耦合生长,并且所得到的微观结构基本上不含初级Si。 考虑到申请人的3HA和3HA合金的耐磨性和汽车应用的机加工性,例如发动机缸体和气缸盖。 受控冷却过程的第一个特征是将冷却剂供应到模具中的上方并从浇口延伸的区域,使得凝固从模具空间的偏远区域均匀地进入浇口,以在整个铸件中产生基本上均匀的微观结构 。 可以使用各种冷却剂,使得门附近的温度比四肢上方的温度高50-75℃。 受控冷却过程的第二个特征是通过在模具的关键控制区域中彼此间隔开的多个浇口将熔体供应到模腔。 使用这种多个门的结果是,积累的能量更广泛地分布在多个关键控制区域中,以便在远程和门区域获得必要的温度,并且在这些控制区域之间达到温差。

    Cast aluminium alloys and method
    4.
    发明授权
    Cast aluminium alloys and method 失效
    铸铝合金和方法

    公开(公告)号:US5217546A

    公开(公告)日:1993-06-08

    申请号:US887395

    申请日:1992-05-21

    IPC分类号: C22C21/04 C22F1/047

    CPC分类号: C22C21/04 C22F1/047

    摘要: A cast hypereutectic Al-Si alloy with from 12-15% Si, having excellent wear resistance and machinability, improved fatigue strength and good levels of ambient and elevated temperature properties is provided, as well as a method of producing such alloy. The alloy and a melt used in the method contains Sr in excess of 0.10% and Ti in excess of 0.005%, the alloy further comprising: Cu 1.5 to 5.5%, Ni 1.0 to 3.00%, Mg 0.1 to 1.0%, Fe 0.1 to 1.0%, Mn 0.1 to 0.8%, Zr 0.01 to 0.1%, Zn 0 to 3.0%, Sn 0 to 0.2%, Pb 0 to 0.2%, Cr 0 to 0.1%, Na 0 to 0.01%, B (elemental) 0.05% maximum, Ca 0.003% maximum, P 0.003% maximum. Others 0.05 maximum each, the balance, apart from incidental impurities, being Al. The level of Sr in excess of 0.10% and Ti in excess of 0.005% is such that the alloy has a microstructure in which any primary Si formed is substantially uniformly dispersed and is substantially free of segregation, and in which substantially uniformly dispersed Sr intermetallic particles are present but are substantially free of such particles in the form of platelets, with the microstructure predominantly comprising a eutectic matrix.

    摘要翻译: 提供了具有12-15%Si的铸态过共晶Al-Si合金,具有优异的耐磨性和可加工性,提高了疲劳强度和良好的环境温度和高温性能,以及制造这种合金的方法。 该方法中使用的合金和熔体含有超过0.10%的Sr和超过0.005%的Ti,该合金还包含:Cu 1.5〜5.5%,Ni:1.0〜3.00%,Mg:0.1〜1.0%,Fe:0.1〜 1.0%,Mn 0.1〜0.8%,Zr 0.01〜0.1%,Zn 0〜3.0%,Sn 0〜0.2%,Pb 0〜0.2%,Cr 0〜0.1%,Na 0〜0.01%,B(元素)0.05 %最大值,最大值为0.003%,最大值为0.003%。 其他0.05,每个最大值,除偶然杂质外,均为Al。 超过0.10%的Sr和超过0.005%的Ti的水平使得合金具有其中所形成的任何主要Si基本上均匀分散并且基本上没有偏析的微结构,并且其中基本上均匀分散的Sr金属间化合物颗粒 存在但基本上没有这样的颗粒形式的颗粒,其中微结构主要包含共晶基质。