半无限体压入的矢量分析与广义积分问题

本文提出一种以矢量分析建立平冲头压入半无限体连续速度场的方法,首次采用广义积分与参变量积分对该速度场求得冲头压力上界解析解。该解以待定参数法确定的最小上界值为n_j=2.85,与三角形速度场最小上界值误差仅为0.7%。     

厚件压缩滑移线场的参变量积分问题

本文提出一种可使厚件压缩获得解析解的参变量积分方法.对传统数值计算找到了φ与y的函数关系,从而可用参量积分求得解析解.l/h=0.121的滑移线场算例表明参量积分结果与数值计算结果基本一致,在理论上表明厚件压缩滑移线场求得解析解完全可能.     

The integral as a function of the upper limit and an analytical solution to plane strain drawing and extrusion

A kinematically admissible velocity field which is different from Avitzur’s is established in Cartesian Coordinates. An upper-bound analytical solution to strip drawing andextrusion is obtained by using the integral as a function of the upper limit in this paper.     

THE INTEGRAL AS A FUNCTlON OF THE UPPER LIMIT AND DEPENDING ON A PARAMETER TO SOLVE DRAWING THROUGH IDLING ROLLS

ＴＨＥＩＮＴＥＧＲＡＬＡＳＡＦＵＮＣＴｌＯＮＯＦＴＨＥＵＰＰＥＲＬＩＭＩＴＡＮＤＤＥＰＥＮＤＩＮＧＯＮＡＰＡＲＡＭＥＴＥＲＴＯＳＯＬＶＥＤＲＡＷＩＮＧＴＨＲＯＵＧＨＩＤＬＩＮＧＲＯＬＬＳＺｈａｏＤｅ－ｗｅｎ（赵德文）；ＺｈａｏＺｈｉ－ｙｅ（赵志业）；...     

两辊串联式辊拔圆丝的理论解析

本文与Hiroshi NAGAI(永井博司)工作的主要区别是我们对辊模压力积分采用精确接触弧方程,得到了辊拔力解析解与摩擦系数有关的不同结论.以积分中值定理与水平力平衡条件确定了辊模压力,并将该解与永井公式进行了比较.     

SOLUTION FOR PLANE STRAIN FORWARD AND BACKWARD EXTBUSIONS WITB A FRACTIONAL REDUCTION R=0.5 BY THE INTEGARTION DEPENDING ON A PARAMETER

A parameter t is introduced to boundary slip line of rigid regions for plane strain and indirect extrusions with a fractional reduction R=0.5. Integration by substitution has been used along the boundary slip line in order to obtain the extrusion pressure. By the integration depending on a pararneter, the following results are obtained, (?)/2R=1.29 and die pressure is 5.14k for backward extrusion, (?)/2R=1.29 and pad average pressure is 2.57k for forward extrusion. All the results from this method are the same as those of the conventional solution.     

余弦模拔制上界速度场的曲线积分问题

余弦模拔制上界速度场的曲线积分问题赵德文，刘相华，张铁（东北大学金属加工系，数学系，沈阳１１０００６）李桂范（辽宁大学数学系，沈阳１１００３６）１．引言对模面为直线的楔形模拔制，［１－３］中讨论了上界解，本文主要工作在于用［１－３］的方法建立模面为余...     

THE INTEGRAL AS A FUNCTION OF THE UPPER LIMIT AND AN ANALYTICAL SOLUTION TO PLANE STRAIN DRAWING AND EXTRUSION

A kinematically admissible velocity field which is different from Avitzur’s isestablished in Cartesian Coordinates.An upper-bound analytical solution to strip drawingand extrusion is obtained by using the integral as a function of the upper limit in this paper.     

管材变壁厚空拉的上界解析解

文章采用柱坐标系推导了与 Avitzur 不同的运动许可三维连续速度场,经极限分析得到管材变壁厚空拉的上界解.     

余弦模拉拔方棒速度场的曲面积分解法

本文对使用余弦模拉拔方棒变形问题,设定了运动许可的三维速度场。证明了该速度场的散度为零且变形区出。入口截面不消耗剪切功率,然后用上界定理与曲面积分方法首次得到了用余弦模拉拔方棒时变形力的解析解。