【作者】 范玲；

【导师】 王克鸿； 武占卿；

【作者基本信息】 南京理工大学 ， 材料工程， 2008， 硕士

【摘要】 电子束焊接作为一种先进的连接技术,在我国制造业中蕴藏着巨大的应用潜力和广阔的开发空间。焊接残余应力是影响构件强度和寿命的主要因素之一,电子束焊接属于局部短时高温加热,焊缝窄而深,在焊接过程中会产生相当大的焊接应力,并在焊后形成残余应力,对结构的安全使用具有重要的影响。随着数值分析、计算机技术和信息技术的迅速发展,数值模拟技术已经逐步渗透到焊接工程问题的研究中,采用有限元方法进行数值模拟焊接残余应力的研究,可以提供一种快捷而又准确的预先研究方法,从而来确定焊接各种结构和材料时的最佳设计、最佳工艺方法和最佳焊接参数。本文以在军事装备、航空航天及其他制造领域中广泛应用的中碳调质钢和纯铝为验证对象,依据热弹塑性理论,采用ANSYS有限元分析软件对平板对接接头电子束焊接残余应力进行数值模拟分析计算,结合金相组织和基本力学性能的分析,研究焊接残余应力的分布特征和数值,同时,采用小孔法对接头残余应力进行了实际测量,将实际测量结果与计算值进行了对比验证,结果表明:焊接残余应力以纵向残余应力为主,纵向残余应力远大于横向残余应力。在焊缝中心处,残余拉应力的峰值低于材料的屈服极限。焊接残余应力模拟结果与试验测量结果基本一致。这说明本文所采用的模拟方法及试验手段具有一定的应用可行性,因此本文的研究成果可以为制定正确的焊接工艺,改善接头性能提供一定的理论依据,从而加速电子束焊接在工程实践中的广泛应用。更多还原

【Abstract】 Electron beam welding have great application potential and broad development space as an advanced technology of joining in China in the manufacturing industry. Welding residual stress is the main affecting factors to strength and life of welding lathes. electron beam welding is a process that the local sector is heated to high temperatures in short-term, Weld seam is narrow and deep ,in the welding process will have a large welding stress, and after welding formation residual stress to the safe use of the structure has important implications.With rapid developing of the numerical analysis, computer technology and the information technology, numerical simulation technology has gradually penetrate into the welding engineering,with the method of finite element to numerical simulate the weld residual stress research that can provide a quick and accurate Advance research methods, to determine the best design, best technological method and best welding parameters in all kinds of structure and welding materials.In this paper, medium carbon hardend tempered steel and aluminum that was used widely in military equipment\aerospace and other industrition is target of studing, according to the thermal elastic and plastic theory, using ANSYS finite element analysis software for residual stress in plate welded joints which was joined with electron beam welding to numerical Analysis, with the analysis of microstructure and mechanical properties, study the distribution and value of welding residual stress, at the same time, measured the joint residual stress with hole drilling method, the actual measurement results Compare for the calculation of the value , The results showed that: welding residual stress is mainly longitudinal residual stress, longitudinal residual stress is far greater than the transversal residual stress. in the Weld center, the maximum value of residual stresses is lower than its yield strength. The simulation results about the welded residual stresses are almost identical with the experimental results by measuring. This shows that the paper used the simulation method and test method have the feasibility of certain applications, the results of research on this paper can be the theoretical basis for the correct welding technology, to improve joint performance ,thereby accelerating the electron beam welding applications widely in engineering.更多还原