We tried using foamcore in school (architecture) in the 70's and found that sometimes it would be ok, but too often, different areas in the sheet would "collapse" from heat/pressure, and you never knew when or where. I don't think it is made with enough consistency for this, and sometimes the sheet had a "low spot" in it before mounting, which would not bond. However, there was a bonding tissue we could use, called Fusion 4000, I think, which worked at a lower temp, and actually fused itself to the two surfaces. It was great stuff, but very expensive. We also bonded with masonite, which we also used for some presentations. We mounted photographs and drawings.