共查询到19条相似文献,搜索用时 125 毫秒
1.
2.
3.
本文叙述了用电阻应变仪,采取切取小段试样法测量了包钢60公斤/米钢轨表面残余应力,及钢轨焊接后残余应力的变化情况,探讨了钢轨残余应力形成的原因,分析了影响钢轨残余应力的各种工艺因素,对比了目前国内外同类型钢轨的残余应力水平,还对目前常用的三种测试方法进行了对比。 相似文献
4.
5.
6.
搅拌摩擦焊接残余应力的研究进展 总被引:1,自引:0,他引:1
搅拌摩擦焊(FSW)是一种新型的固态焊接技术。作为一种新技术,还存在着许多问题需要更深入广泛地研究,如材料的流动、温度场、接头的残余应力等。本文介绍了FSW残余应力的试验测量方法和有限元数值模拟方法的研究进展,以及FSW接头残余应力控制技术,分析了接头残余应力的影响因素,揭示了FSW焊接接头残余应力分布的一般规律。 相似文献
7.
P110套管冷矫残余应力模拟分析 总被引:5,自引:0,他引:5
残余应力是影响套管抗挤强度的主要因素之一,为了分析矫直对套管残余应力分布的影响,应用有限元分析软件Marc建立了P110套管冷矫模型,通过模拟计算,得到了套管截面环向残余应力分布状况,将模拟结果与实际测量结果进行了对比。模拟的结果表明经过冷矫的套管存在很大的残余应力。 相似文献
8.
简要介绍了场致扩散连接的机理、特点及应用,指出了残余应力的存在对键合质量的影响。在分析金属一陶瓷场致扩散连接中残余应力产生原因的基础上,给出了降低这些因素影响的具体措施。 相似文献
9.
为分析大气等离子喷涂Al2O3-40%Ti O2复合陶瓷涂层在冷却过程中涂层崩裂的现象,本文采用有限元方法,研究了涂层内部残余应力分布情况,探讨了涂层厚度、孔隙、裂纹等因素对残余应力的影响。结果表明:基体与粘结层和粘结层与涂层的界面边缘处出现了应力集中区域,随着X尺寸(模型水平方向的距离)的增加,涂层及粘结层内部应力由压应力转变为拉应力;涂层厚度只对残余应力值有影响,对应力分布状态影响较小,随着涂层厚度的增加,X向(径向)应力逐渐增加,Y向(轴向)应力及剪切应力在界面边缘处急剧变化;大孔隙、纵向裂纹对涂层残余应力影响较大。有限元模拟分析较好的解释了涂层在冷却过程中涂层层状崩裂的现象。 相似文献
10.
11.
12.
13.
Xiaoya Dai Wenlong Zhang Ping Gao Shaozong Zhang Mingyuan Gu Hua-Xin Peng 《Metallurgical and Materials Transactions A》2014,45(3):1559-1566
The relationship between pretension and residual stress of an aluminum wire reinforced with 45 vol pct continuous Nextel? 610 alumina fibers is investigated. It is shown that as pretension stress increases, the matrix residual stress decreases. A transition in matrix residual stress from tension to compression occurs at a pretension stress of about 80 MPa. The initial rapidly decreased residual stress caused by pretension at relatively low pretension stresses is a result of matrix elastic compressive deformation; while the later gradually decreased residual stress at higher pretension stresses comes from matrix plastic compressive deformation. As the matrix yield stress and hardening exponent increase, the decrease in matrix residual stress with pretension stress is more rapid and the absolute value of matrix residual stress increases. An analytical model suitable for fiber-reinforced metal matrix composites (MMCs) with strong interfacial bonding is developed to describe the relationship between pretension and matrix residual stress and is shown to be in good agreement with the experimental and finite-element calculated results. The pretension-dependent matrix residual stress phenomenon suggests that the mechanical properties of fiber-reinforced MMCs associated with matrix residual stress may be effectively improved by applying tensile loads. 相似文献
15.
陶瓷与金属由于在热膨胀系数上的差异,导致在热加工后结合强度较差。冷喷涂是一种新型绿色环保的表面涂层和增材制造技术,其优点是结合强度较高,对基体热影响小,残余应力为压应力,能够直接在陶瓷表面制备结合力较高的金属涂层,是一种潜在的陶瓷金属化技术。本文综述了国内外冷喷涂陶瓷金属化技术的研究进展和技术现状,着重介绍了冷喷涂陶瓷金属化涂层的组织结构特点和工艺优化方案,分析了金属陶瓷界面的两种结合现象和结合机理,并展望了冷喷涂陶瓷金属化技术的应用设想。 相似文献
16.
研究了铝与玻璃的阳极连接方法,采用公共阳极法和直流电源实现了玻璃/铝/玻璃的多层连接,这为多层晶片的连接以及复杂微电子装置的没计提供方法和理论基础.通过SEM、EDS和GD-OES分析手段分析了玻璃/铝的结合界面.采用instron-5544万能材料试验机进行拉伸实验发现断裂发生在玻璃基体中,这表明界面的结合强度高于玻璃基体的强度,SEM断口形貌分析表明断裂界面呈贝壳状的解理断面,说明运用公共阳极可以实现多层晶片的良好键合.实验表明在温度为350℃ ~ 450℃,电压在为400~ 800V时,玻璃-铝-玻璃的键合质量较高. 相似文献
17.
周飞 《中国稀土学报(英文版)》2001,(2)
Bondingofsiliconnitrideceramicswithoxideglasssolderhasbeenachievedverygreatsuccess[1~ 11] .Owingtothelowersofteningtemperatureofresidualglassinjoint ,thehightemperaturestrengthofjointhasbeendeterio rated .Inordertoimprovethejointstrengthatelevatedtemperatu… 相似文献
19.
《Acta Metallurgica Materialia》1994,42(8):2657-2673
Transverse mechanical properties have been measured, and damage mechanisms identified, in three Ti3Al matrix composites with different interface compositions and residual stress states. Two of the composites contained SiC fibers with weak interfaces. Large improvements in transverse strength and rupture strain were found in one of these composites, in which brittle reaction products in the matrix around the fibers had been avoided by coating the fibers with Ag and Ta before consolidation. The third composite contained sapphire fibers that were strongly bonded to the matrix. Different damage mechanisms were observed in the strongly and weakly bonded composites. Insight into the damage mechanisms and their dependence on residual stress fields and interface properties is gained from comparison of the observations with analytical solutions of elastic stresses. The conditions for optimum transverse properties are discussed; the results indicate that strong interfacial bonding does not necessarily lead to optimum transverse strength of the composite. 相似文献