Currently metals can be welded to metals and glass to glass, but the two don't mix well. They require different temperatures to melt and they expand differently in response to the heat. There are other manufacturing methods to get them to stick together, but they aren't quit as neat.
"Being able to weld glass and metals together will be a huge step forward in manufacturing and design flexibility," says Duncan Hand, director of the EPSRC Centre for Innovative Manufacturing in Laser-based Production Processes, which developed the new technique. "At the moment, equipment and products that involve glass and metal are often held together by adhesives, which are messy to apply and parts can gradually creep, or move. Outgassing is also an issue – organic chemicals from the adhesive can be gradually released and can lead to reduced product lifetime."
The new technique works on optical materials such as quartz, borosilicate glass and sapphire, which can now be welded to metals like aluminum, stainless steel and titanium. The key to the process was an infrared laser that fires pulses on the scale of a few picoseconds – trillionths of a second.