硝子面の傷について
1: 鋼刃でつけた硝子面の傷
1961 年 30 巻 2 号 p. 86-92
詳細
1961 年 30 巻 2 号 p. 86-92
Scratch on glass surface made by sliding of a steel edge is studied. Microscopic and phasemicroscopic observations are made before and after acid treatment.
The scratch generally has two different parts. One is the destroyed part consisting of cracks that are cavities filled with air readily recognizable by the naked eye or under microscope. The other is the region where glass has been turned into an abnormal state by severe stress. Such a region can be recognized by phase-microscopy or by chemical “developing”.
An explanation is proposed of the shape of the cracks, wich is based on qualitative analysis of the stress. It is inferred that some tensile strain is permanently left in the “abnormal” region.
