低合金低溫用鋼的焊接性
低(di)合金低(di)溫(wen)鋼中碳(tan)≤0.2%,同時(shi)合金元素的總質量分數不超過(guo)5%,碳(tan)當(dang)量較(jiao)(jiao)低(di),淬硬(ying)傾向較(jiao)(jiao)小,因(yin)此冷(leng)裂敏感性(xing)不大。薄板(ban)焊接(jie)時(shi)一(yi)(yi)般(ban)(ban)可(ke)不預熱,但(dan)應避(bi)免在低(di)溫(wen)下(xia)施焊。當(dang)板(ban)厚超過(guo)25mm或焊接(jie)接(jie)頭的拘束較(jiao)(jiao)大時(shi),應采用適當(dang)的預熱措施,以防止焊接(jie)冷(leng)裂紋,但(dan)預熱溫(wen)度(du)不能過(guo)高,一(yi)(yi)般(ban)(ban)控制...