在过去几年中,国外发展了不少难熔合金,主要发展高温抗氧化合金,而在焊接方面进展却不大。由于宇宙航行和国防工业的需要,美国一些科研单位对难熔金属的焊接进行了研究。近年来,美国政府投之于巨额研制空间渡船,并正加紧发展多弹头分导导弹,除发 In the past few years, a lot of foreign countries have developed refractory alloys, mainly the development of high temperature oxidation resistant alloys, but little progress has been made in welding. Due to the needs of the aerospace and defense industries, some research institutes in the United States have studied the welding of refractory metals. In recent years, the U.S. government has invested heavily in the development of space ferries and is stepping up efforts to develop multi-warhead sub-missile systems.