The fused silica glass direct bonding consists in joining two surfaces without using any adhesive. This technology is used in particular to manufacture optical systems like optical slicers or interferometers used in terrestrial optics. The final aim of this investigation consist to spatialize this technology. But the spatial environment is totally different from the terrestrial one. A satellite may undergo shocks, vibrations or thermal fatigue. It is necessary to characterize with accuracy the direct bonded interface under these solicitations to respect the European Space Agency requirements.

In this context, a new test machine has been developed to characterize interface shock resistance. The new machine design is based on two principles. The first one, the Arcan assembly modified developed by Cognard, consists in loading an adhesively-bonded assembly with different loading types, tensile mode or shear mode. It is constituted by two half disks with several attachment points on their periphery. These attachment points allow installing the mount on a standard tensile testing machine. The second, the Beevers and Ellis testing machine, imposes a tension load on a specimen by the falling weight along a tube connected to the specimen. In our concept, we replaced the specimen in Beevers and Ellis machine by the Arcan assembly.

A test campaign on the fused silica glass direct bonding has been performed with the new experimental device. The specimens are solicited by shocks in pure traction and shear mode. The aim consists in measuring the fracture energy. This energy is calculated in function of the mass and the drop height, and for all tests the drop height is the same to keep a constant speed. In order to complete the dynamic study, a static study is performed with the Arcan device on a standard testing machine in traction, shear and a mixed mode (I+II).