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The research states and applications of refractory metals tungsten, molybdenum, tantalum, niobium and rhenium and their alloys and coatings used in spaceflight industry, have been summarized. The kinds, mechanical properties and preparation technologies of the alloys and performances of their coatings have also been introduced. The refractory metals are mainly used as rocket engine and spacecraft structural parts. And the tungsten, molybdenum and their crystals are also used in space dynamical system. The order of the service temperature from high to low in refractory metals and their alloys is same as the melting point order of materials.