平板玻璃受热后折射率的变化规律初探

目的探索平板玻璃受热后折射率的变化规律。方法首先采用差示扫描量热仪测定玻璃样品的转变温度Tg,将样品加热至不同的温度(温度范围从室温到Tg以上),自然冷却至室温后再用GRIM3测量折射率。结果加热温度在Tg以下时,玻璃的折射率基本不变,加热温度在Tg以上时,折射率有明显变化。结论对于从火灾和爆炸现场提取的玻璃,在进行折射率比对时应当考虑现场高温对测量值的影响,并进行必要的修正。

Variation of the refractive indices of the plate glass after heat treatment

Objective To measure the plate glass refractive indices and find its changeable regularities after heat treatment. Methods Using DSC7 to measure the glass change temperature (Tg), heat the specimen to different degree (from room temperature to Tg up ) , after natural cooling-off, then using GRIM3 equipment to measure the refractive index. Results The effects of low temperature (below Tg) to glass refractive indices can been seen as zero, that of high temperature (above Tg) is very critical. Conclusion We must think over the effects of the temperature at scene when using the refractive indices to identify the glass recovered from fire scene.