The glass gets stronger as the temperature lowers. This is true of any amorphous material. The actual breakage point of any glass object is strongly dependent on the surface condition. breakage initiates in small scratches on the surface. Also the Chemical composition of any surface coat has a...
I would agree with Kirby Wan. There are quite a number of glass and glass ceramic seals that would stand the temperature, but I would be very cautious about the longer term resistance to the thermal cycling. You might also think about a graded seal to lower the thermal stresses at the crtical...
An excellent source of such information is Konrady's "Applied Optics and Optical Design" This is an old classic that has been reprinted by Dover publications and it is very clear and understandable and covers your topic very well.
It would help quite a bit if you gave a little more information. i.e.
temperature range.
glass composition or type at least roughly
Are you concerned with strength? (increases over quite a range )Are you asking about impact resistance etc.?
Surface contamination is the root of most bonding problems as you probably know. I would get a SEM and a scan for surface elements. I would also try Boron Nickel. That sometimes bonds better.
Given your size constraints I would use a glass frit sealant formulated for stainless steel. These fire at about 600C. Owens Illinois makes several that bond by forming a new oxide between the glass and metal. This is green and opaque, but will be restricted to the region of the seal. You will...
My 60 year old swimming pool houses the filter in a 14" diameter copper pot that extends 26" below ground. The soil here is decomposed granite which is quite acidic and eats copper. The copper pot has developed many pinholes and is ready to fail. I propose to line it with one or two layers of 30...