(哈爾濱工業(yè)大學(xué) 現(xiàn)代焊接生產(chǎn)技術(shù)國(guó)家重點(diǎn)實(shí)驗(yàn)室，
哈爾濱 150001)
摘 要: 將攪拌摩擦焊接過(guò)程中材料的流動(dòng)看作是層流、 粘性、 非牛頓流體繞過(guò)旋轉(zhuǎn)的圓柱體， 并基于流體力學(xué)理論， 建立了二維攪拌摩擦焊縫金屬塑性流動(dòng)的數(shù)值分析模型。計(jì)算結(jié)果表明： 只有很少一部分靠近攪拌頭探針的材料在焊接過(guò)程中受到探針的作用而發(fā)生變形， 直接影響到材料的流動(dòng)； 在大多數(shù)的模擬條件下， 探針直徑范圍內(nèi)的材料僅僅在回撤邊一側(cè)沿旋轉(zhuǎn)方向繞過(guò)探針，而不是在探針兩側(cè)繞流； 繞過(guò)探針以后， 焊縫金屬材料又以恒定的速度， 繼續(xù)向前移動(dòng)； 變形區(qū)域內(nèi)流變材料的流動(dòng)速度大于探針直徑范圍外流變材料的流動(dòng)速度。 采用“標(biāo)記嵌入技術(shù)”對(duì)焊縫金屬流動(dòng)進(jìn)行了可視化研究，并對(duì)實(shí)驗(yàn)結(jié)果與模擬結(jié)果進(jìn)行了驗(yàn)證， 模擬結(jié)果能很好地預(yù)測(cè)塑性金屬流動(dòng)趨勢(shì)。
關(guān)鍵字: 攪拌摩擦焊； 流動(dòng)； 數(shù)值模擬； 2014鋁合金
welding process
（State Key Laboratory of Advanced Welding Production Technology,
Harbin Institute of Technology, Harbin 150001, China）
Abstract: The material transport in the welding process was regarded as a laminar, viscous and non-Newtonian liquid flows past a rotating cylinder pin. Based on fluid mechanics a two-dimensional friction stir welding (FSW) process model was developed. The results of the simulation show that just a little material close to the pin is affected during the welding process, and the material has experienced extreme deformation. Material within the pin diameter passes the pin only on the retreating side in the rotation direction and not on both sides of the pin. The speed of the material in the region affected by the pin is faster than the material outside of the deformed region. Material flow visualization experiments of “marker insert technology” are used to validate the simulated results. The experimental images agree well with the simulated results and the two-dimensional model predicts many of the trends observed in the experiments.
Key words: friction stir welding; flow; numerical simulation; 2014Al alloy
