Scientists of the Glass Group at the Laser Zentrum Hannover (LZH) have developed a process for laser-based joining of borosilicate and quartz glass.
Complex glass parts are, in most cases, manufactured manually by a glass apparatus maker using a gas flame. Since the process cannot be entirely controlled, the quality fluctuates. LZH’s process includes integrated temperature control that regulates the viscosity of the parts in a pre-defined way during the welding process.
The process uses a CO2 laser beam to provide the required amount of heat energy. The temperature is measured without contact using a pyrometer.
In order to bridge gaps at, for example, L angle geometries, glass powder is added as filler material during the joining process. In doing so, the glass powder is melted and forms a homogeneous welding seam with a constant bead height. The new process setup enables automated joining of glass in various welding configurations, such as butt joints, fillet joints and L angles.
The project was supported by the German Federation of Industrial Research Associations.