To glue silicone rubber to metal.
How to glue silicone foam mat.
Silicone can be glued but you often need a special surface activator chemical to prepare the silicone and the substrate to be bonded.
Rough the silicone rubber and the metal with a low grit coarse sand paper.
Liberally apply adhesive coating both pieces and allow about 10 seconds for the glue to become tacky.
Spray a solvent based activator accelerator aa on either the silicone rubber or metal.
Since you are working with foam mats you can slice into the foam to give more contact area for the adhesive.
People like permabond and loctite can do them.
Silicone glue works best on silicone rubber.
The silicone glue is an adaptable bonding and sealing adhesive that allows you to manipulate foam rubber as the glue dries.
Warm the polypropylene surface with a hair dryer or heat gun.
Epoxy silicone vinyl caulk and many other glues and adhesives will work.
Bonding the foam together.
It is fairly easy to obtain at hardware or big box home improvement stores.
Applying glue to a small piece of foam place the two pieces of cushion foam that need to be glued on top of each other with the sides to be adhered facing outward as shown to the lower left.