This week, scientists at heriot-watt University claimed to have used a groundbreaking method that USES ultra-fast lasaer pointer pulses to weld together materials such as glass and metal.
Traditionally, welding has been limited to materials with similar properties. At present, equipment and products involving glass and metal are usually held together by adhesives, which are troublesome to use and can cause parts to come loose or move. Gas release is also a problem – the gradual release of organic chemicals from binders can shorten product life.
Duncan Hand, director of the EPSRC laser manufacturing process innovation manufacturing center, says the key to the new technology is an infrared laser that fires pulses within picoseconds. When the parts to be welded are in close contact, the laser is focused through the optical material, providing a very small, high-intensity spot of light at the interface between the two materials.
The team tested welds at temperatures ranging from -50°C to 90°C (-58°F to 194°F), and the welds remained intact.
The new technology is suitable for optical materials such as quartz, borosilicate glass and sapphire, which can now be welded to metals such as aluminium, stainless steel and titanium.