在Extralite官网闲逛时看到的，自己一直很感兴趣陶瓷轴承，觉得本文有点意思就转载过来了。翻译水平一般，欢迎指正。欢迎转载，请注明译者。
原文地址：http://www.extralite.com/Tips/bearings%20tips.htm
Full-ceramic Bearings
Among bike enthusiasts have tried to employ full-ceramic bearings in order to save weight and further reduce rolling resistance. Unfortunately with today's technology a properly dimensioned steel bearing cannot be replaced with a full-ceramic bearing of the same dimensions. Size should increase commensurately when moving from steel to ceramic and this nullifies any weight savings and requires a specifically designed hub-shell.
Additional note: even full-ceramic bearing manufacturers are openly not recommending their products for bicycle applications due to the ceramic material's fragility. Typical bicycle applications involve high impact resistance at low rpm (10-100 rpm) while the typical full-ceramic bearing application is at very high rpm (over 20,000 rpm) and absorbs only low impacts.
全陶瓷轴承
许多自行车爱好者经常使用全陶瓷轴承来减轻重量以及减少滚动阻力。不幸的是，在当今科技之下，一个适当尺寸的钢轴承无法被同样尺寸的陶瓷轴承替换。当变更轴承时，尺寸应该相当的增加。然而增大尺寸抵消了节约的重量，并且需要特殊设计的花鼓壳体。
额外注解：即使全陶瓷轴承生产商也不公开推荐他们的产品用于自行车上，由于陶瓷易碎的属性。寻常自行车应用涉及高冲击阻力于一个较低的转速（10-100RPM），然而典型的全陶瓷轴承应用于高转速（大于20，000RPM）以及吸收很小的冲击。
Load ratings of ceramics bearings
Ceramic has a modulus of elasticity higher than that of high carbon chrome bearing steel. In the ceramic bearing, therefore, less deformation on the rolling elements (balls or rollers) generates higher stress at the contact point between the rolling element and raceway, when compared to a steel bearing.
陶瓷轴承的荷载评定
陶瓷的形变系数高于碳铬轴承钢的形变系数。因此，在陶瓷轴承里，相比于钢轴承，更小的形变导致更高的压力于内环和滚珠的接触点上。
Therefore, the contact stress between rolling elements and races of ceramic bearing would be significantly higher than that of steel bearing, under the same amount of load.
因此，在同样的荷载之下，陶瓷轴承的滚珠和内环之间的接触压力会显著高于钢轴承的。
Load ratings of ceramic bearings compared to steel bearings.陶瓷轴承荷载评定，对比钢轴承
The load capacity of ceramic bearings is accordingly decreasing when working temperature is increasing. HSC suggests choosing a larger load rating capacity bearing when using a full ceramic bearing for your application. Due to the brittleness of ceramics, full ceramic bearings are not capabale of withstanding too much impact load. The outer races or inner races will generate cracks or even suddenly break under a certain amount of impact load.当运行温度上升时，陶瓷轴承的负载能力显著下降。HSC（是天朝的哦）建议，当使用全陶瓷轴承时，选择较大的负载能力的轴承。由于陶瓷易碎，全陶瓷轴承无法承受太多冲击负载。内圈或者外圈会产生裂纹或者在受到一定程度冲击时突然碎裂。
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结论就是，陶瓷很脆，不耐冲击，所以全陶瓷轴承不适合自行车(个人估计也许后拨导轮可以用)。更换混合轴承的前提是，本身轴承足够大（强度冗余足够），以及不是用于冲击特别大的场合。FIN
