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未来航天飞行器上的推进系统要求材料比当前所用的更轻、在高温下具有更高的强度和刚度。发动机重量的减轻和对冷却要求的减少可带来以下好处。首先可得到更高的推力和重量比,其次由于操作温度增高可得到更大的热力效率。有序的金属间化合物,如Ti_3Al,NiAl,FeAl和NbAl_3等具有优异的抗氧化和抵抗环境作用的能力、高的熔点和相对低的密度,因此可成为先进航天飞行器上有希望的材料,然而由于这些材料在低温下的韧性差和
Future propulsion systems on spacecraft require materials that are lighter than currently used and have higher strength and stiffness at high temperatures. Engine weight reduction and cooling requirements reduction can bring the following benefits. First, higher thrust and weight ratios are available, followed by greater thermal efficiency due to higher operating temperatures. Ordered intermetallics such as Ti_3Al, NiAl, FeAl and NbAl_3 have excellent resistance to oxidation and environmental effects, high melting points and relatively low densities, making them promising materials for advanced aerospace vehicles. However, Due to the poor toughness of these materials at low temperatures