本文選題：鋁粉 + 等徑角擠扭��； 參考：《Transactions of Nonferrous Metals Society of China》2015年07期

【摘要】：采用3D有限元模擬、實(shí)驗(yàn)研究和理論分析,并在與傳統(tǒng)等徑角擠壓工藝對(duì)比基礎(chǔ)上,系統(tǒng)研究擠扭成形對(duì)等徑角擠扭工藝固結(jié)純鋁粉末-包套過(guò)程的影響。模擬結(jié)果表明,在等徑角擠扭法固結(jié)純鋁粉末-包套過(guò)程中,擠扭成形起反向背壓作用,螺旋通道所提供的旋轉(zhuǎn)剪切變形和高靜水壓力可大幅增加材料內(nèi)部的塑性剪切應(yīng)變,顯著改善變形坯料的變形均勻性。在內(nèi)角為90°、螺旋角為36.5°的方形截面通道模具上,經(jīng)200℃下1道次等徑角擠扭變形實(shí)驗(yàn),成功將純鋁粉末顆粒固結(jié)為近致密的塊體材料。有限元模擬與實(shí)驗(yàn)結(jié)果具有較好的一致性。顯微組織觀察和硬度測(cè)試實(shí)驗(yàn)結(jié)果表明,等徑角擠扭法固結(jié)的塊體材料晶粒更加細(xì)小,孔隙得到有效收縮焊合,組織性能均勻性更好。這是由于在等徑角擠扭變形過(guò)程中劇烈剪切應(yīng)變大大增加,同時(shí)擠扭成形所起的反向背壓作用有效提高了Al原子的自擴(kuò)散系數(shù)。
[Abstract]:By using 3D finite element simulation, experimental study and theoretical analysis, and on the basis of comparing with the traditional equal diameter angle extrusion process, the influence of the process of consolidation of pure aluminum powder and sheath on the process of extrusion and torsion forming by equal diameter angle extrusion and torsion process is systematically studied. The simulation results show that in the process of consolidation of pure aluminum powder by equal path angular extrusion and torsion method, the extrusion and torsion forming plays a reverse back pressure role, and the rotational shear deformation and high hydrostatic pressure provided by the spiral channel can greatly increase the plastic shear strain inside the material. The deformation uniformity of the deformed billet is improved obviously. On the square cross section die with 90 擄internal angle and 36.5 擄spiral angle, the pure aluminum powder particles were successfully consolidated into a compact bulk material by 1 pass of secondary diameter angle extrusion and torsional deformation experiment at 200 鈩，

本文編號(hào)：2042960