Gear Materials (Reading Material)齿轮 材料（阅读 材料）Gears are manufactured from a wide variety of materials, both metallic as well as nonmetallic.齿轮 由多种种类 的材料制造，包括金属材料和非金属材料。As is the case with all materials used in design, the material chosen for a particular gear should be the cheapestavailable that will ensure satisfactory performance.在设计 中可以使用多种材料的情况下，对 于特定齿轮 ，应 当做到选 用满 足使用要求下的最便宜的材料。Before a choice is made, the designer must decide which of several criteria is most important to the problem athand.
