【摘要】：在對(duì)激光焊接過程中匙孔壁面受力平衡狀態(tài)和金屬蒸發(fā)情況研究基礎(chǔ)上,建立了隨匙孔深度和形貌變化的自適應(yīng)熱源模型。采用Particle Level Set方法來跟蹤熔池內(nèi)的匙孔自由表面,對(duì)2A12合金和30CrMnSiA鋼激光深熔焊過程進(jìn)行了數(shù)值模擬,分析了材料性能和側(cè)吹氣體對(duì)熔池-匙孔內(nèi)的溫度場(chǎng)、流場(chǎng)和匙孔動(dòng)態(tài)演化過程的影響。研究結(jié)果表明,相同工藝參數(shù)下熱導(dǎo)率較小的材料,更容易形成深而窄的焊縫形貌。而側(cè)吹氣流氣體的加入不僅能夠改善熔池內(nèi)流體的流動(dòng)狀態(tài),而且能夠顯著地抑制焊縫中氣孔產(chǎn)生。在此基礎(chǔ)上,利用熔池動(dòng)態(tài)監(jiān)測(cè)技術(shù)對(duì)激光焊接中熔池的動(dòng)態(tài)行為進(jìn)行了實(shí)驗(yàn)觀測(cè),得到了熔池內(nèi)匙孔頸縮、塌陷、閉合以及氣泡的形成過程,進(jìn)一步驗(yàn)證了模擬結(jié)果的合理性。在對(duì)不同側(cè)吹氣流下焊縫氣孔檢測(cè)和模擬結(jié)果分析的基礎(chǔ)上,提出了增強(qiáng)焊接穩(wěn)定性和降低氣孔敏感性的新思路。
[Abstract]:Based on the study of the stress balance state and metal evaporation of the keyhole wall during laser welding, an adaptive heat source model with the variation of the depth and morphology of the keyhole was established. The Particle level set method is used to track the free surface of keyhole in the molten pool. The process of laser deep fusion welding of 2A12 alloy and 30CrMnSiA steel is numerically simulated. The material properties and the temperature field of side blowing gas in the weld pool and keyhole are analyzed. The influence of the flow field and the dynamic evolution of the keyhole. The results show that it is easier to form deep and narrow weld morphology of materials with lower thermal conductivity under the same process parameters. The addition of side blowing gas can not only improve the flow state of the fluid in the molten pool, but also significantly inhibit the formation of pores in the weld. On this basis, the dynamic behavior of molten pool in laser welding is observed by using the technology of dynamic monitoring of molten pool. The process of necking, collapsing, closing and bubble formation of keyhole in molten pool is obtained. The rationality of the simulation results is further verified. Based on the analysis of gas hole detection and simulation results of weld under different side blowing flow, a new way of improving welding stability and reducing porosity sensitivity is put forward.
【作者單位】： 中國(guó)工程物理研究院總體工程研究所;
【基金】：國(guó)家自然科學(xué)基金(11372295) 中國(guó)工程物理研究院重大基金(2013A0203008);中國(guó)工程物理研究院重點(diǎn)學(xué)科項(xiàng)目“計(jì)算固體力學(xué)”資助
【分類號(hào)】：TG456.7
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本文編號(hào)：2136050