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镁合金笔记本电脑外壳的温成形技术研究 邱恺1,朱文峰3,徐春1 (1.上海应用技术学院材料工程系,上海,200235;2.重庆理工大学材料科学与工程学院,重庆,400050;3.同济大学机械工程学院,上海,200092) 摘要:采用0.6mm厚的AZ31镁合金材料,以温成形方式获得了复杂外形尺寸的笔记本电脑外壳.通过研究温度对AZ31镁合金板料拉深成形性能的影响发现:180~280℃成形的镁合金电脑外壳零件不会出现断裂和起皱缺陷,但角部高度随成形温度的升高而增加;低于180℃成形,零件圆角出现褶皱;高于280℃成形,圆角被拉裂;并且成形速度和摩擦也会影响零件成形. 关键词:AZ31镁合金; 温成形; 成形温度; 拉深; AZ31 magnesium alloy; warm forming; forming temperature; drawing; [全文内容正在添加中] ......
forming 1.1.1 弹性起皱失稳分析 管坯外压缩径原理如图1所示.选用柱坐标系分析缩径过程中的起皱失稳现象.图1中,x为变形区轴向坐标;r为径向坐标;θ为环向坐标.缩径过程中管坯成形区体积被压缩,设ω,u,v分别为筒壁中性层任意点径向,轴向,环向的位移,假设管坯任一截面环向屈曲形态满足余弦波分布,则位移表达式为  ...起皱失稳的影响. 图10 模具照片及缩径工艺原理示意图 Fig. 10 Die photo (a) and schematic diagram of principle of SGMF tube outer pressure compression forming (b) 2.3 试验结果 工艺试验得到的成形零件照片如图11所示,图中L为缩径区高度,N为皱纹波......
后沿其表面扩散;随着扩散时间的延长,Al与Sn元素间扩散和溶解程度增大,界面区无新物相生成,最终形成由Al和Sn的离异合金组织组成的界面过渡层且呈锯齿状形态分布;Al/Sn界面冶金结合是Al和Sn固相扩散,溶解与结晶共同作用的结果.关键词:Al/Sn;扩散偶;界面;扩散溶解层;形成机理Forming mechanism of diffusion couple of Al/Sn interphase...)Abstract:The diffusion couples of Al/Sn were prepared by laminating diffusion couple technology, and then treated for different holding times. The appearance characteristics and forming mechanism of Al/Sn......
Improving effect on forming quality and accuracy using a polyurethane board positioning/resetting the discrete steel pad in multi-point formingEr-hu Qu1,2,3,Ming-zhe Li1,2,31. College of Materials Science and Engineering,Jilin University2. Roll Forging Institute,Jilin University摘 要:To improve the quality of multi-point die forming, a new approach using......
Influence of viscous medium temperature distribution on sheet fracture in viscous pressure forming at warm temperature LIU Jian-guang(刘建光)1, WANG Zhong-jin(王忠金)1, ZHANG Xin(张鑫)2, LI Yi(李毅)1 1... pressure forming (VPF) of aluminum alloy AA3003 sheet metal at warm temperature was investigated by using coupled thermo-elastoplastic-viscoplastic finite element method. The influence of viscous......
away from the curve obtained from bulging through circular die. The forming limit diagram in the range of positive minor strain of a DC04 sheet steel is also determined by using bulge test. Key words: hydraulic bulge test; stress-strain curves; forming limit diagram 1 Introduction The most important advantage of the hydraulic bulge test is the absence of the contact (the frictional interactions......
Effect of extrusion wheel angular velocity on continuous extrusion forming process of copper concave bus bar WU Peng-yue(吴朋越)1, XIE Shui-sheng(谢水生)1, LI Hua-qing(李华清)1, YAN Ming(鄢 明)1, HUANG...; Abstract: The continuous extrusion forming process for producing large section copper concave bus bar under different extrusion wheel......
有少量非晶,且主要呈晶体组织特征. 关键词:非晶合金;镁合金;块体金属玻璃;玻璃形成能力 中图分类号:TG 139.8 文献标识码:A Effect of Nd on glass forming ability of bulk amorphous Mg-Cu-Y-Nd alloys WU Shu-sen, LIU Wei, MAO... diffractometry, the effect of Nd on glass forming ability of Mg-Cu-Y-Nd was analyzed. The results show that the samples with x of 0, 4 and 6 are bulk metallic glass, and the best glass forming ability (GFA......
] GOODWIN G M. Application of strain analysis to sheet metal forming problems in the press shop[R]. Chicago: Society of Automobile Engineers, 1968. [2] ISO 12004-2: 2008. Metallic materials-sheet and strip determination of forming limit curves-part 2: determination of forming limit curves in laboratory[S]. [3] ASTM E2218-02. Standard test method for determining forming limit curves[S]. [4] MARCINIAK Z......
:TG146.2 文献标志码:A Effect of Al on glass forming ability and thermal stability of Mg-Cu-Y alloys NING... solidification method. Then the samples were annealed at various temperatures. The effects of Al on the glass forming ability (GFA) and thermal stability of Mg80-xAlxCu15Y5(x=0,1) alloys were studied by XRD......