材料选择英文文献和中文翻译(3)

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1. Easier creation and correction of drawings. Working drawings may be created more quickly than by hand and making changes and modifications is more efficient than correcting drawings made by hand.

2. Better visualization of drawings. Many systems allow different views of the same object to be displayed and 3D pictorials to be rotated on the CRT screen.

3. Database of drawing aids. Creation and maintenance of design databases (libraries of designs) permits storing designs and symbols for easy recall and application to the solution of new problems.

4. Quick and convenient design analysis the designer can evaluate alternative design thereby considering more possibility while speeding up the process at the same time.

5. Simulation and testing of designs. Some computer systems make possible the simulation of a product's operation, testing the design under a variety of conditions and stresses; computer testing may improve on or replace construction of models and prototypes.

6. Increased accuracy. The computer is capable of producing drawings with more accuracy than is possible by hand; Many CAD systems are even capable of detecting errors and informing the user of them.

7. Improved filing. Drawings can be more conveniently filed, retrieved, and transmitted on disks and tapes.

Computer graphics has an almost limitless number of applications in engineering and other technical fields. Most graphical solutions that are possible with a pencil can done on a computer and usually more productively. Applications vary from 3D modeling and finite element analysisi4] to 2D drawings and mathematical calculations.

Once the domain of large computer systems advanced applications can now be done on microcomputer. An important extension of CAD is its application to manufacturing. Computer-aided design/computer-aided manufacturing (CAD/CAM) systems may be used to design a part or product, devise the essential production steps, and electronically communicate this information to and control the operation of manufacturing equipment, including robots. These systems offer many advantages over traditional design and manufacturing systems, including less design effort, more efficient material use, reduced lead times, greater accuracy, and improved inventory control.

材料选择

在近年来工程材料的选择已经承担了巨大的重要性。此外，过程应该是一个持续的重新评估。新材料经常成为可用，而其他人可能会减少可用性。对环境污染，循环再造和工人健康和安全的关注往往强加给新的限制。对减轻重量或节约能源的愿望可能决定使用不同的材料。来自国内外的竞争压力，增加舒适度的要求，和客户的反馈，都可能促使人们对材料进行重新评价。产品责任行为的程度，往往是由于材料使用不当造成的，有着明显的影响；此外，材料与加工之间的相互依赖关系也越来越好。新流程的开发往往力量被加工材料的再评价。因此，设计和制造工程师在选择，指定和利用材料，如果他们是在合理的成本，并保证质量，以达到令人满意的结果，必须行使相当的照顾。

在制造任何产品的第一步是设计，通常发生在几个不同的阶段：（一）概念；（乙）功能；（三）生产设计。在概念设计阶段，设计师主要关心的是产品的功能，通常是可视化和考虑的几个概念，并作出决定，要么是不可行的想法是声音和一个或多个概念设计应进一步发展。在这里，唯一关心的材料是材料的存在，可以提供所需的财产。如果没有这样的材料，考虑是否有一个合理的前景，可以开发新的成本和时间的限制。