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2¼Cr-1Mo steels have been used in power and chemical plants for elevated temperature high pressure components since the 1930's. Recent concerns involving the service of submerged arc (SA) welded steam piping has resulted in the inception of this study. Because welded piping may be either annealed and tempered (A&T), normalized and tempered (N&T) or subcritically postweld heat treated (PWHT), the aim of this study was the determination of the elevated temperature properties of 2¼Cr-1Mo weldments subjected to these heat treatments after welding. The significance of chromium differences was investigated in addition to the determination of stress rupture properties in the different heat treated conditions. Characterization of the microstructure using analytical techniques indicated that the stability of carbides in the ferritic or bainitic microconstituents dictate the elevated temperature properties of the weld metal. Regions which are stronger than the soft zone appearing in the welds exert a constraint effect thereby limiting the rupture potential. Publication of this document - WRC Bulletin No. 405 - was sponsored by the Materials and Fabrication Division of the Pressure Vessel Research Council