ABS与铝合金搅拌摩擦焊工艺研究

发布时间：2018-05-15 11:56

  本文选题：搅拌摩擦焊 + 工艺优化　； 参考：《兰州理工大学》2016年硕士论文

【摘要】：由于现代经济严重依赖于石化能源的消耗,因此导致能源供应日趋紧张、环境压力加剧。经济社会的发展要求节能减排,而汽车轻量化是我国节能减排战略环节中较为重要的一部分,其中轻量化应用新材料包括铝合金、镁合金、钛合金、高性能塑料、多孔发泡及复合材料等。搅拌摩擦焊对于焊接材料适用范围广泛,同时也能够焊接物理性能差异巨大的异种材料。因此,本文将搅拌摩擦焊技术应用于ABS高分子塑料的焊接、ABS与铝合金的焊接。工艺试验结果表明,搅拌摩擦焊可以实现非金属塑料ABS、ABS与6082铝合金的焊接。为了验证搅拌摩擦焊对非金属塑料的焊接适用性,采用搅拌摩擦焊技术焊接ABS塑料。工艺试验结果表明当转速为1300r/min、下压量为0.15mm、焊接速度为20mm/min,可以实现ABS对焊的有效连接。接头强度可达到20.5MPa,达到母材的68%,焊缝前进侧与后退侧表面形态趋近一致,表面无明显的毛刺与未融合白化现象。采用搅拌摩擦搭接点焊焊接ABS塑料,工艺参数对接头力学性能影响因素主次为:停留时间转速下压量。上、下板结合面处,断面较为平整,分子链端实现了有效的融合与交联。焊点出现分层现象并且断裂始于混合分层和上、下板材结合面处。采用搅拌摩擦点焊焊接ABS与铝合金时,搅拌头是否有搅拌针对点焊连接的影响区别较大。焊后焊点表面均较为平整,成形美观,可以实现6082与ABS可靠连接。但是在不同焊接工艺下最优焊接参数不同,且抗拉剪载荷差距明显。这是由于无搅拌针焊接接头最高温度比有针焊接拌头温度高100℃,因此无匙孔焊接接头连接面积大于后者,最终使得前者接头强度高于后者。对比接头断裂位置发现,接头均断裂与ABS一侧。以最优焊接参数焊接时,接头出现两种断裂模式:剥离断裂和ABS母材塑性断裂,其中ABS母材塑性断裂包括,沿着焊点结合面向两端扩展断裂,沿焊点边缘位置沿直线线外扩展断裂两种形式。接头断裂经历了3个阶段:裂纹萌生、稳定扩展、快速扩展,在拉剪破坏过程中形成了有明显区别的裂纹扩展花样,第三阶段在断面上裂纹扩展速度最快。点焊断裂破坏起源于铝合金和ABS轴间边缘结合界面的气泡缺陷与微裂纹。点焊接头的结合力来自于两种材料接触界面的分子力与机械结合力包括,ABS分子与铝合金表面、Al2O3氧化物在摩擦热的作用下发生交联固化,形成分子间结合力;树脂分子链端与铝合金铝原子、表面氧化物互相在另一材料基体上“钉扎”获得的机械结合力。
[Abstract]:Because the modern economy depends heavily on the consumption of fossil energy, the energy supply becomes increasingly tight and environmental pressure intensifies. The development of economy and society requires energy saving and emission reduction. Automobile lightweight is an important part of the strategy of energy saving and emission reduction in China. The new materials of lightweight application include aluminum alloy, magnesium alloy, titanium alloy, high performance plastics, etc. Porous foaming and composite materials. Friction stir welding (FSW) is widely used for welding materials, and it can also be used to weld dissimilar materials with great difference in physical properties. Therefore, friction stir welding (FSW) technology is applied to the welding of ABS polymer plastics and aluminum alloy. The experimental results show that friction stir welding can realize the welding of non-metallic plastics ABSS-ABS and 6082 aluminum alloy. In order to verify the applicability of friction stir welding (FSW) to non-metallic plastics, friction stir welding (FSW) was used to weld ABS plastics. The experimental results show that the ABS butt welding can be realized effectively when the rotational speed is 1300 r / min, the lower pressure is 0.15 mm and the welding speed is 20 mm / min. The strength of the joint is up to 20.5 MPa, and the weld metal is 68. The surface morphology of the forward and backward sides of the weld seam is close to the same, and there is no obvious burr and no whitening on the surface. Friction stir spot welding (FSW) was used to weld ABS plastics. The main and secondary factors affecting the mechanical properties of the joints were as follows: the pressure under the residence time and rotational speed. The cross section of the upper and lower plate is smooth, and the molecular chain end can be effectively fused and crosslinked. The solder joint appears delamination and fracture begins with mixed delamination and upper and lower plate bonding. When friction stir spot welding (FSW) is used to weld ABS and aluminum alloy, the effect of stir head on spot welding joint is different. After welding, the surface of solder joint is flat and the shape is beautiful. 6082 and ABS can be connected reliably. However, the optimal welding parameters are different in different welding processes, and the difference between tensile and shear loads is obvious. This is due to the fact that the maximum temperature of the welded joint without stirring needle is 100 鈩，

本文编号：1892371