塑料 冲击脆化温度的测定

[中文适用范围]： 本国际标准规定了测定在正常环境温度下非刚性的塑料在规定的冲击条件下表现出脆性破坏的温度的方法。 使用缺口样品的补充技术在比相同塑料材料的无缺口样品观察到的温度高得多的温度下产生脆性值。 该方法利用统计技术来量化脆性失效温度。 规定测试足够的样品，以便在统计基础上计算脆性温度。 已经开发出统计技术来量化 3.1 中定义的脆性温度。 该方法确定了无缺口或缺口样本失效概率为 50% 的温度。 人们发现该方法对于规范目的很有用，尽管它不一定测量材料可以使用的最低温度。 在脆性温度的测量中，在确定材料规格中使用的值时，测量精度最差最好为±5CC。 [外文原描述]： This International Standard specifies a method for the determination of the temperature at which plastics that are not rigid at normal ambient temperature exhibit brittle failure under specified impact conditions. A supplementary technique using notched specimens develops brittleness values at a much higher temperature than are observed for unnotched specimens of the same plastic material. The method utilizes a statistical technique to quantify the brittleness failure temperature. Provisions are made for the testing of sufficient specimens to permit the calculation of the brittleness temperature on a statistical basis. Statistical techniques have been developed to quantify the brittleness temperature as is defined in 3.1. The method establishes the temperature at which there is a 50 % chance of failure in either unnotched or notched specimens. This method has been found useful for specification purposes, although it does not necessarily measure the lowest temperature at which the material may be used. In the measurement of the brittleness temperature, the precision of the measurement should preferably be _ 5 °C at the worst when establishing values used in material specifications.