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钨(wu)是(shi)(shi)熔(rong)(rong)(rong)点(dian)最高(gao)(gao)(gao)(gao)的(de)难熔(rong)(rong)(rong)金(jin)(jin)属。一般熔(rong)(rong)(rong)点(dian)高(gao)(gao)(gao)(gao)于(yu)1650℃并有(you)(you)(you)一定储 量(liang)的(de)金(jin)(jin)属以及熔(rong)(rong)(rong)点(dian)高(gao)(gao)(gao)(gao)于(yu)锆熔(rong)(rong)(rong)点(dian)（1852℃）的(de)金(jin)(jin)属称为(wei)难熔(rong)(rong)(rong)金(jin)(jin)属。典(dian)型(xing)的(de)难熔(rong)(rong)(rong)金(jin)(jin)属有(you)(you)(you)钨(wu)、钽(tan)、钼、铌、铪、铬(ge)、钒、锆和(he)钛。作为(wei)一种(zhong)难熔(rong)(rong)(rong)金(jin)(jin)属，钨(wu)最重要的(de)优点(dian)是(shi)(shi)有(you)(you)(you)良好(hao)的(de)高(gao)(gao)(gao)(gao)温(wen)强度(du)，对(dui)熔(rong)(rong)(rong)融碱金(jin)(jin)属和(he)蒸气有(you)(you)(you)良好(hao)的(de)耐蚀性(xing)(xing)能，钨(wu)只(zhi)有(you)(you)(you)在(zai)1000℃以上才出现氧化物(wu)挥发(fa)和(he)液相氧化物(wu)。但是(shi)(shi)，它(ta)同时也具有(you)(you)(you)塑性(xing)(xing)－脆(cui)性(xing)(xing)转变温(wen)度(du)较高(gao)(gao)(gao)(gao)，在(zai)室温(wen)下(xia)难以塑性(xing)(xing)加工的(de)缺点(dian)。以钨(wu)为(wei)代表的(de)难熔(rong)(rong)(rong)金(jin)(jin)属在(zai)冶(ye)金(jin)(jin)、化工、电(dian)子、光源、机械工业等部门得到了(le)广泛应用。