A process for bonding a porous material having an opened porous cellular structure to a substrate material, the process including the steps of: conditioning the substrate with tantalum in a reactor at 925.degree. C. having a tantalum source pot at 550.degree. C.; affixing the porous material to the conditioned substrate to form an affixed composite structure by clamping the porous material to the conditioned substrate; and, subjecting the composite structure to a chemical vapor deposition process (CVD) which uses tantalum as a source material for a time sufficient to CVD bond the porous material to the conditioned substrate material.