某厂聚碳酸酯电源钮在使用过程中发生批量断裂。通过宏微观分析、红外分析、气相色谱-质谱联用（GC-MS）分析和弯曲性能测试等方法，分析了聚碳酸酯电源钮的断裂原因。结果表明：断裂电源钮发生了脆性断裂，断裂的原因是电源钮材料中含有少量的丙烯腈-丁二烯-苯乙烯共聚物（ABS），降低了电源钮的弯曲强度，而含有卤代烃的润滑剂渗入电源钮中，导致电源钮的强度进一步降低，最终导致其发生低应力脆断。

Polycarbonate power button of a factory broken in batches during use. The causes of fracture on polycarbonate power button were analyzed by means of macro and micro analysis, infrared analysis, gas chromatography-mass spectrometry (GC-MS) analysis and bending property test. The results show that the fracture power button occured brittle fracture. The reason for the fracture was that there was a small amount of acrylonitrile-butadiene-styrene copolymer (ABS) in the power button material, which reduced the bending strength of power button. Besides, the lubricant containing halogenated hydrocarbon seeped into the power button, which led to the further decrease of strength of power button, and finally led to low stress brittle fracture.