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钨(wu)(wu)是(shi)熔(rong)(rong)(rong)点(dian)最高(gao)的(de)难熔(rong)(rong)(rong)金(jin)(jin)(jin)(jin)属。一(yi)般熔(rong)(rong)(rong)点(dian)高(gao)于1650℃并有(you)(you)(you)一(yi)定(ding)储 量的(de)金(jin)(jin)(jin)(jin)属以(yi)(yi)及熔(rong)(rong)(rong)点(dian)高(gao)于锆(gao)(gao)熔(rong)(rong)(rong)点(dian)（1852℃）的(de)金(jin)(jin)(jin)(jin)属称(cheng)为(wei)难熔(rong)(rong)(rong)金(jin)(jin)(jin)(jin)属。典型的(de)难熔(rong)(rong)(rong)金(jin)(jin)(jin)(jin)属有(you)(you)(you)钨(wu)(wu)、钽、钼、铌(ni)、铪、铬(ge)、钒、锆(gao)(gao)和钛。作为(wei)一(yi)种难熔(rong)(rong)(rong)金(jin)(jin)(jin)(jin)属，钨(wu)(wu)最重要的(de)优(you)点(dian)是(shi)有(you)(you)(you)良好的(de)高(gao)温(wen)强(qiang)度，对熔(rong)(rong)(rong)融碱金(jin)(jin)(jin)(jin)属和蒸气有(you)(you)(you)良好的(de)耐蚀(shi)性能，钨(wu)(wu)只有(you)(you)(you)在(zai)1000℃以(yi)(yi)上才出(chu)现氧化(hua)物挥发和液(ye)相氧化(hua)物。但是(shi)，它同时也具有(you)(you)(you)塑(su)(su)性－脆性转变(bian)温(wen)度较高(gao)，在(zai)室温(wen)下难以(yi)(yi)塑(su)(su)性加工(gong)(gong)的(de)缺点(dian)。以(yi)(yi)钨(wu)(wu)为(wei)代表(biao)的(de)难熔(rong)(rong)(rong)金(jin)(jin)(jin)(jin)属在(zai)冶金(jin)(jin)(jin)(jin)、化(hua)工(gong)(gong)、电子、光源(yuan)、机械工(gong)(gong)业等(deng)部门得(de)到了(le)广泛(fan)应用。