本文關(guān)鍵詞： QC低合金高強(qiáng)鋼 等匹配 低碳貝氏體 全自動MAG焊 貝氏體回火　出處：《焊接學(xué)報(bào)》2015年01期 　論文類型：期刊論文

【摘要】：為提高效率、獲得理想斷裂位置并改善熱影響區(qū)韌性,對控扎控冷工藝生產(chǎn)的8 mm厚Q690C低碳粒貝鋼,選用等強(qiáng)度匹配的焊絲,采用無預(yù)熱、低熱輸入(10 k J/cm以下)三層全自動MAG工藝施焊.結(jié)果表明,無裂紋與成形缺陷;拉、彎與沖擊性能均合格.焊縫為針狀鐵素體,韌性優(yōu)異;僅在較窄的部分相變區(qū)(單道約0.2~0.4mm)因回火而出現(xiàn)軟化,但未對抗拉性能形成危害;因熱輸入低,拉伸斷裂位置距焊縫更遠(yuǎn);雖然熔合區(qū)與粗晶區(qū)為粗大平行上貝板條束+M-A組元,出現(xiàn)了硬化,但低熱輸入的低過熱效果與兩次后續(xù)焊道對貝氏體基體的明顯回火作用改善了熔合區(qū)在0℃的沖擊韌性.
[Abstract]:In order to improve the efficiency, obtain the ideal fracture position and improve the toughness of the heat affected zone, the 8mm thick Q690C low carbon grain beige steel produced by the controlled zoning and cooling process was selected as the welding wire with equal strength matching and without preheating. The three-layer fully automatic MAG process with low heat input less than 10kJ / cm is applied. The results show that there are no cracks and forming defects. The tensile, bending and impact properties are all qualified. The weld is acicular ferrite with excellent toughness. Only in the narrow partial phase transition zone (about 0.2 ~ 0.4mm single channel) softened due to tempering, but did not harm the tensile properties. Because of the low heat input, the tensile fracture position is farther away from the weld. Although the fusion zone and the coarse crystal region are coarse parallel to the upper shell strip beam M-A component appears hardening. However, the low superheating effect of low heat input and the obvious tempering of bainite matrix by two subsequent welding passes improved the impact toughness of the fusion zone at 0 鈩，

本文編號：1479834