  High-purity glasses are used for their low optical and mechanical loss, which
makes them an excellent material for oscillators in optical systems, such as
inertial sensors. Complex geometries often require the assembly of multiple
pieces of glass and their permanent bonding. One common method is hydroxide
catalysis bonding, which leaves an enclosed medium layer. This layer has
different mechanical properties to the bulk glass around it. The higher
mechanical loss of this layer makes it more susceptible to displacement noise
originating from the conversion of energy from oscillation to heat and vice
versa. Therefore, other methods are needed to bond together glass assemblies.
To investigate this, we have set up an experiment to measure the mechanical
losses of several different types of bond commonly used in fused silica
manufacturing, namely; plasma activated direct bonding, hydroxide catalysis
bonding, laser welding, and adhesive bonding. In this paper we present the
experimental design and show initial results of the first test sample.
