Heat treatment behavior and tensile properties of Cr-W steels

The author discusses ferritic steels containing Cr, W, and V being developed for fusion reactor applications. These steels would be alternatives to the Cr-Mo steels that are being considered for structural components. Eight experimental steels were produced. Chromium concentrations of 2.25, 5, 9, and 12 pct were used. Steels with these chromium compositions and with 2 pct W and 0.25 pct V were produced. To determine the effect of tungsten and vanadium, 2.25Cr steels were also produced with 2 pct W and no vanadium, and with 0.25 pct V and zero and 1 pct W. A 9Cr steel containing 2 pct W, 0.25 pct V., and 0.07 pct Ta was also studied. For all alloys, carbon was maintained at 0.11 pct. Tempering behavior of the steels was similar to that of the Cr-Mo steels being considered. Tensile studies indicate that the 2.25Cr-2W-0.25V and 9Cr-2W-0.25V-0.25V-0.07Ta steels had the highest strengths with properties similar to those of the 9Cr-1MoVNb and 12Cr-1MoVW steels, which are the strongest of the Cr-Mo steels of interest