Abstract
The resistance to hydrogen induced disbonding of rolled clad steel was investigated by thermal hydrogen charging in autoclave for the development of heavy gauge rolled Cr-Mo clad steel with higher resistance to disbonding.
Rolled clad steels are shown to have better resistance to disbonding than conventional overlay welded clad steels both in single and multi hydrogen charging. Formation of martensite caused by dilution with base steel, and precipitation of carbide on grain boundary of cladding weld metal caused by carbon migration from base metal are the main causes for the decrease of resistance to disbonding in overlay welded clad steel, which would be suppressed in rolled clad steels utilizing solid phase bonding.
Further improvement of resistance to disbonding in rolled clad steels can be achieved by decreasing the microvoids at the interface and the addition of V to base metal. Good resistance to disbonding can be maintained even after head plate forming and welding.
