【正文】 ighspeed railway is developing rapidly, aluminum alloy with good plasticity, easy shaping, lightweight, corrosionresistant was used widely in the highspeed train. Welding technology as a very important molding technology was widely used in the manufacture of highspeed trains. Welding process involved the producing electric arc, plex heat transfer, phase change of metal, welding deformation and residual stresses and other plex phenomenon. In the process of welding, highdensity transient heat input, local heating, the heat source relative motion makes the welder heated uneven, resulted in great stress and deformation, thus made a bad effect on the Thermal and mechanical properties of the workpiece, so studying temperature field and stress field of the welding process have a decisive significance on the quality of welded structures. With the rapid development of puter technology and related business software development, finite element simulation has bee an important means of studying the welding technology. In this paper, we has SYSWELD, a largescale mercial software as a platform. We bined with the actual welding method and process to simulate temperature and stress fields in the actual welding conditions, and pared with temperature and stress fields measured from the experiments in the same condition. Then we find that i t verifies the accuracy and feasibility of the numerical simulation software SYSWELD. After that, We simulated temperature and stress fields of 100mm, 200mm, 400mm, 800mm weldment with the same other conditions. We found that the temperature field and stress field stay in a stable state in the middle of the weldment if the weldment e to a length. the longer the weldment, the longer the stable state stays. This provides a enough theoretical basis to simplify the modeling and simulation of the aluminum side wall of the highspeed train. We can shorten the length of sidewall model with The above simulation as a theoretical basis, and reduce the putational significantly without affecting the software simulation results. We have three conditions to simulate： one is welding the two lines at the same time； second is welding the second line right after welding the first line； third is welding the second line after the first line cooling for a period of time。 After simulation，we got temperature and stress fields, and find that the third condition is better than the first and the second condition. We still find that the first condition got a higher temperature and stress. So we suggest that the enterprise consider the results of the study in the manufacturing. Keywords: Finite element。Numerical simulation。Temperature field。 Stress field 西南交通大學(xué)本科 畢業(yè)設(shè)計(jì) (論文 ) 第 VI 頁 目 錄 第 1 章 緒論 ........................................................................................................................... 1 本論文研究的意義 ...................................................................................................... 1 焊接溫度場和應(yīng)力場數(shù)值模擬的國內(nèi)外歷史及發(fā)展現(xiàn)狀 ............................................... 2 焊接溫度場數(shù)值模擬國內(nèi)外歷史及發(fā)展現(xiàn)狀 ...................................................... 2 焊接應(yīng)力場數(shù)值模擬國內(nèi)外歷史及發(fā)展現(xiàn)狀 ....................................................... 4 論文的主要工作內(nèi)容 ................................................................................................... 5 第 2 章 有限元數(shù)值理論基礎(chǔ)和軟件應(yīng)用 .................................................................................. 7 有限元分析理論基礎(chǔ) ................................................................................................... 7 有限元理論 ....................................................................................................... 7 焊接過程溫度場有限元分析理論 ........................................................................ 7 焊接過程應(yīng)力場有限元分析理論 ...................................................................... 10 軟件應(yīng)用 .................................................................................................................. 11 模型建立和網(wǎng)格劃分 ....................................................................................... 11 熱源調(diào)節(jié) ......................................................................................................... 13 Welding Advisor 建立工程 ................................................................................. 19 后期處理并分析 ............................................................................................... 20 熱源調(diào)節(jié)的經(jīng)驗(yàn) ........................................................................................................ 20 第 3 章 SYSWELD 模擬溫度場和應(yīng)力場實(shí)驗(yàn)驗(yàn)證 .................................................................. 24 鋁合金材料堆焊的熱循環(huán)實(shí)驗(yàn) ................................................................................... 24 實(shí)驗(yàn)簡介 ......................................................................................................... 24 熱電偶測溫原理 .............................................................................................. 25 測量焊件上的幾個典型點(diǎn)的溫度 ...................................................................... 25 焊接模擬溫度場的計(jì)算結(jié)果和實(shí)驗(yàn)驗(yàn)證 ..................................................................... 25 焊縫中心線點(diǎn)的溫度時間變化過程 .................................................................. 26 垂直焊縫方向點(diǎn)的溫度時間變化過程 ............................................................... 27 溫度場的實(shí)驗(yàn)驗(yàn)證 ........................................................................................... 28 鋁合金材料的應(yīng)力值測量實(shí)驗(yàn) ................................................................................... 29 小孔法簡介 ..................................................................................................... 29 應(yīng)力值測量 ..................................................................................................... 30 焊接模擬應(yīng)力場的計(jì)算結(jié)果和實(shí)驗(yàn)驗(yàn)證 ...................