Progressive damage modelling of SMC composite materials

The present work deals with the modelling of damage behaviour for sheet moulding compound (SMC) composite materials using a finite element analysis package. Specifically, a comparison is made between the results obtained experimentally for a three-point bending test, and those obtained from numerical simulation using a material model already implemented. The simulation has been performed for the material models available within the PAM-CRASH software. The simulation results are compared and validated with respect to experimentation.     

Universal Rendering Sequences for Transparent Vertex Caching of Progressive Meshes

We present methods to generate rendering sequences for triangle meshes which preserve mesh locality as much as possible. This is useful for maximizing vertex reuse when rendering the mesh using a FIFO vertex buffer, such as those available in modern 3D graphics hardware. The sequences are universal in the sense that they perform well for all sizes of vertex buffers, and generalize to progressive meshes. This has been verified experimentally.     

深孔薄壁件挤压模CAD系统

介绍了利用ActiveXAutomation技术，以VB为开发工具，并采用参数化绘图研究开发的深孔薄壁件挤压模CAD系统。     

Axisymmetric extrusion through adaptable dies—Part 1: Flexible velocity fields and power terms

An adaptable die is one that not only produces the correct geometrical shape, but also is designed through an adaptable method to impart other desirable properties to the product or process. In this first part of a series of papers, six kinematically admissible velocity fields are developed for use in upper bound models for axisymmetric extrusion through various dies, including extrusion through adaptable dies. Three base velocity fields are presented:

(1) assuming proportional angles in the deformation zone,

(2) assuming proportional areas in the deformation zone, or

(3) assuming proportional distances from the centerline in the deformation zone.

The base velocity is modified by an additional term comprised of two functions. One function allows extra flexibility in the radial direction, and the second function allows extra flexibility in the angular direction. There are two forms of the second function, which meet the required boundary conditions. The flexibility function in the radial direction is represented by a series of Legendre polynomials, which are orthogonal over the deformation region. The power terms derived for these velocity fields for use in upper bound models are also presented.Part 2 of this series compares the results obtained in upper bound models for the six velocity fields for a spherical extrusion die. In Part 3, the use of the best velocity field for extrusion through streamlined dies is developed to determine the adaptable die shape, which minimizes the required extrusion pressure. Additionally, the adaptable die shape is compared with results from Yang and Han for arbitrarily curved and streamlined dies.     

锌基合金模具的应用及探讨

本文分析了锌基合金模具制造及使用过程中容易出现热裂、翘曲、收缩的问题，并提出了解决这些问题的措施。     

A case study: California utilities and the progressive business model

Concentration on the new technological and funding requirements for decarbonizing utilities has obfuscated the reality that there is a new utility business model. The Progressive Business Model is legislation and regulatory actions taken to address climate change. Lacking a feedback loop for policy correction, it has raised utility rates, coopted utility management’s operational and investment independence, and sacrificed ratepayer safety and reliability.     

试论ISO9000在我国压铸工业中的实施

介绍了ＩＳＯ９０００标准中２０项质量管理规范，对其中的主要条款，结合压铸生产的需要作了说明，提出了我国压铸企业在质量管理方面如何与国际接轨的具体内容和方向。     

纺机织轴边盘的金属型低压铸造

介绍了采用金属型低压铸造生产边盘所涉及的设备、模具、工艺 ,并对产品质量和经济效益进行了分析     

真空压铸的发展

真空系统是压铸过程中排除气体的最有效的方法之一。然而，真空压铸的发展几经起伏，现在则发展到一个新的阶段。从模具中抽出气体是几种抽气方法中较为简便的一种。真空气道的设计与常规气道则有所不同     

铝合金车轮铸造模具CAD/CAE技术的应用

随着计算机应用技术的发展，CAD/CAE技术已广泛应用于各行各业的设计，主要介绍了铝合金年轮铸造模具上应用CAD/CAE技术的成效。