A method of treating a substrate by applying a layer of at least one metal to the substrate to form an applied metal layer on the substrate and followed by curing of the applied metal layer at sub-atmospheric pressure to form a metal protective layer. A method of treating a substrate by applying a layer of at least one metal to a substrate of an unassembled component of a reactor system to form an applied metal layer on the substrate of the unassembled component and curing the applied metal layer on the substrate of the unassembled component to form a metal protective layer. A method of treating a substrate by applying a layer of at least one metal to the substrate to form an applied metal layer, curing the applied metal layer at a first temperature and pressure for a first period of time, and curing the applied metal layer at a second temperature and pressure for a second period of time, wherein the curing forms a metal protective layer.