Producing titanium-sapphire items by solid-phase bonding through aluminum gasket

The high mechanical, optical and other properties of sapphires make then very attractive for numerous practical applications. Production of titanium sapphire compositions through aluminum gaskets to make tools to be used at 500 C and 10 MPa pressure is discussed. Alloys VT1-0, VT6S and VT16 and L-V leucosapphire disks and slugs were bonded and polished, then tested for strength and useful life. Results showed minimal mechanical strength at 540 C, 2 MPa and 5 minutes of welding, but strength increased thereafter up to 5 MPa, 630 C and 40 minutes. Above those values, mechanical strength declined as surface defects and residual stress weakened the bonds. Titanium sapphire orifices of 50 mm were subjected to heating and cooling (20-500-20 C at 20 C/min) and to pressures of up to 10 MPa, without damage.