Numerical Analysis of Stable Melting Pool Penetration for Aluminum Alloy wheel Frame TIG Welding Technique

• Main Authors: Wei, Zong-Ying, 魏宗潁
• Other Authors: Chang, Chin-Lung
• Format: Others
• Language: zh-TW
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/6tk3jp

碩士 === 國立屏東科技大學 === 車輛工程系所 === 106 === This work used TIG (tungsten inert gas) welding technique to weld aluminum alloy wheel frame with the finite element analysis software ABAQUS .The process parameters were tried to change to achieve the goal of stable melting pool penetration. The process parameters of TIG welding consists rotating speed of rotary table, current of tungsten bar, initial temperature of work piece(aluminum alloy wheel frame)and current duration on initial position of welding. The simulation results showed that if this study used the initial process parameters to be set, the result could not achieve the wanted goal. The failure factor was found as follows: First of all, current duration on each position of welding was too long that led to overheat at end of welding path on work piece. Therefore, the goal could not be accomplished. But this question could be modified by building up the rotating speed of rotary table. Because when the rotating speed of rotary table increases that means the current duration on each position of welding will be decreased. It also means this method could not led to overheat on work piece. Next, melting pool penetration was not deep enough due to most of heat source energy (tungsten bar) will be absorbed by work piece. When TIG welding technique was used to weld workpiece(aluminum alloy wheel frame), the energy of heat source will be conducted and absorbed by it. Therefore, we could not accomplish the stable weld depth goal which we wanted. But we could increase current duration on initial position of welding to solve this question. It could be better that if the preheating was treated at initial position of welding on work piece. And then we could obtain the goal that a stable weld depth. This study got two optimization cases under rotating speed of rotary table at 2 rpm and 3 rpm by changing process parameters. It could increase current duration on initial position of welding or increase current value of tungsten bar to get enough welding depth. But we had to do preheating treatment for work piece before TIG welding under rotating speed of rotary table at higher speed (3 rpm). Hence, a stable welding depth could be obtained at high rotating speed utilizing the preheating treatment on workpiece.