包亦望
,
刘正权
无机材料学报
doi:10.15541/jim20150444
钢化玻璃应用广泛,但其自爆问题是一个被称为玻璃癌症的难题,其特征是突发性和灾难性,因此如何减少和预防预测玻璃自爆是钢化玻璃工程应用领域的关键问题.本文重点探讨了钢化玻璃的自爆机理,揭示了钢化玻璃为什么会自爆,什么条件下可能自爆和各种影响玻璃自爆的内在与外在因素.研究发现由于杂质和缺陷引起的应力集中是导致自爆的关键因素,证明钢化玻璃内部的残余应力和局部强度均是非线性分布,局部强度在玻璃表面最高,中间层最低,自爆的根本原因是内部的应力集中超过了局部强度,而传统认识的硫化镍或单质硅等各种杂质只是引起自爆的间接原因.提出的钢化玻璃自爆准则为玻璃破碎分析提供了有用的参考.
关键词:
钢化玻璃
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自爆
,
局部强度
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残余应力
Y.W.Bao
,
Y.F.Han
,
F.T.Gong
金属学报(英文版)
Stress relaxation of glass is a dualism effect, it often lead to strength degradation in strengthened glass, but on the other hand, it improves the reliability and stressuniformity of glasses. In this work, stress relaxation of soda-lime glass was investigated using three-point bending tests at 400-560℃ which is near the brittle to ductile transition temperature, for enhancing the safety of glass productions and exploring the most economic anneal process. The experimental results show that the speed of stress relaxation increases but the ultimate stress decreases with increasing temperature. The stress uniformity of the glass samples before and after anneal was examined using spherical indentation at arranged testing points. It indicates that the scatter of the local strength measured by the Hertzian indentation is smaller in the anneal glass than in initial specimen, so that the estimated Weibull modulus for the anneal specimen is higher. Furthermore, the strength evaluation by Hertzian indentation and statistical analysis was presented.
关键词:
glass
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null
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