Boron-silicon glass (also known as hard glass) is a glass that is used to conduct electricity under high temperature conditions. Glass is melted by heating inside the glass and processed by an advanced production process. The coefficient of thermal expansion of the wire is (3.3 ± 0.1). ) × 10-6/K, also known as "borosilicate glass 3.3". It is a special glass material with low expansion rate, high temperature resistance, high strength, high hardness, high light transmittance and high chemical stability. Due to its excellent performance, it is widely used in solar energy, chemical industry, pharmaceutical packaging, electric light source. , craft jewelry and other industries. Its good performance has been widely recognized by all walks of life in the world, especially in the field of solar energy applications, Germany, the United States and other developed countries have carried out more extensive promotion.