玻璃中只要存在温度差就会产生热应力,温度随时间变化,经过一段时间后将会使玻璃产生热疲劳损伤,而降低其力学性能。本文主要研究无约束热疲劳,依据大量的试验,研究了Weibull模数m和特性强度σ_0随热循环次数变化的规律,并探讨了在热疲劳情况下,玻璃表面微裂纹的萌生和扩展。 As long as there is temperature difference in glass, it will generate thermal stress, temperature changes with time, after a period of time will make the glass thermal fatigue damage, and reduce the mechanical properties. In this paper, we mainly study unconstrained thermal fatigue. Based on a large number of experiments, the law of the Weibull modulus m and the characteristic intensity σ_0 with the number of thermal cycles are studied. The initiation and propagation of microcracks on the glass surface under thermal fatigue are also discussed.