SGER: Synthesis and Consolidation of Nickel Aluminide Powder

SGER资助的重点是一种基于机械铣削的新加工技术，该技术涉及铣削过程中的化学反应。该方法消除了通常需要从副产品盐中分离金属的传统浸出过程。这个过程包括引入铝作为还原剂，代替镁、钙或钠。起始原料是金属氯化物，副产品氯化铝可以用真空蒸馏代替浸出分离，从而消除通常注意到的表面氧化。概念验证将在用铝从氯化镍开始加工铝化镍时进行检验。所得到的粉末在稍高的温度下被压实，从而得到细晶粒的合金。该方法制备NiAl的工艺温度低，副产品价值高，具有较好的经济效益。该技术一旦得到证实和建立，将适用于其他广泛应用于高温结构材料的铝化物。在机械化学反应中使用Al作为还原剂的新技术消除了通常需要的第二步浸出，这一步骤通常会导致表面氧化。该工艺一旦被证明是有效的，就可以用于加工许多其他纯度更高的金属合金，同时大幅降低成本。

The focus of the SGER grant is on a new processing technique based on mechanical milling that involves chemical reaction during milling process. The method eliminates the traditional leaching process that is usually required to isolate the metal from by-product salts. The process involves introducing aluminum as a reducing agent, in place of Mg, Ca or Na. The starting material is metal chloride and the by-product aluminum chloride can be separated by vacuum distillation in lieu of leaching thereby eliminating the usually noted surface oxidation. The proof-of-concept will be checked in processing nickel aluminide starting from nickel chloride with aluminum. The resulting powder is consolidated by pressing at slightly high temperatures that will result in fine-grained alloy. The production of NiAl by this new method will be very cost-effective because of the low processing temperature and the valuable by-product. The technique once proven and established will be applicable for other aluminides that find extensive application as high-temperature structural material.The new technique of using Al as a reducing agent during mechanochemical reaction eliminates the usually required second step of leaching that in general results in surface oxidation. This process once proven effective can be adopted for processing of many other metal alloys with superior purity along with substantial cost reduction.