奧氏體不銹鋼的縫焊,其焊接(jie)(jie)接(jie)(jie)頭(tou)的力(li)學性能、焊接(jie)(jie)質量(liang)及焊接(jie)(jie)條(tiao)(tiao)件等,都與點焊一(yi)樣。選擇焊接(jie)(jie)條(tiao)(tiao)件時(shi),因為母材的高(gao)強(qiang)度(du)高(gao),應采用(yong)(yong)較(jiao)高(gao)的電(dian)(dian)極壓(ya)力(li)來抑制產生(sheng)焊接(jie)(jie)缺(que)陷(xian)。通電(dian)(dian)時(shi)間宜短(duan),通電(dian)(dian)中電(dian)(dian)極移(yi)動距離要(yao)(yao)小。通電(dian)(dian)時(shi)間短(duan),電(dian)(dian)流(liu)(liu)強(qiang)度(du)就要(yao)(yao)加大,電(dian)(dian)極的消(xiao)耗就加快。若是(shi)斷(duan)(duan)續通電(dian)(dian),斷(duan)(duan)電(dian)(dian)時(shi)間應是(shi)通電(dian)(dian)時(shi)間的兩倍以上。若斷(duan)(duan)電(dian)(dian)時(shi)間或(huo)者(zhe)焊接(jie)(jie)速度(du)慢(man),可能因為分(fen)流(liu)(liu)作用(yong)(yong),在(zai)焊接(jie)(jie)下一(yi)個點時(shi),使前一(yi)個焊點再熔化,可能因為對該點已(yi)經不受壓(ya)力(li)而產生(sheng)缺(que)陷(xian)。
要想得到(dao)致密的(de)(de)縫焊(han)(han)接(jie)頭,除應當選用(yong)合適的(de)(de)焊(han)(han)接(jie)電(dian)流外,還要調整焊(han)(han)接(jie)速度(du)及(ji)通(tong)/斷電(dian)時間(jian)。要使焊(han)(han)點的(de)(de)重(zhong)復量(liang)達到(dao)焊(han)(han)點直徑(jing)的(de)(de)10%~25%。表3-33所示為奧(ao)氏體不銹(xiu)鋼(gang)的(de)(de)焊(han)(han)接(jie)條件。由于不銹(xiu)鋼(gang)的(de)(de)熱傳導不良及(ji)電(dian)阻率較大(da),所以(yi),連續(xu)通(tong)電(dian)比斷續(xu)通(tong)電(dian)對母材的(de)(de)熱影響大(da),變形(xing)也(ye)大(da)。電(dian)極(ji)材料(liao)適用(yong)RWMA的(de)(de)2級(ji)或3級(ji),電(dian)極(ji)端部要平或者梯(ti)形(xing)。


