Patent ID: 8317944

Claim:
A 9 Cr-1 Mo steel having a tempered martensite microstructure and comprised of Fe, 8.0-13.0 wt. % chromium, 0.5-1.5 wt. % molybdenum, 0.05-0.15 wt. % carbon, and 0.05-0.2 wt. % titanium, where the 9 Cr-1 Mo steel material is comprised of primary TiC grains and secondary TiC grains, where a mass ratio of primary TiC grains to secondary TiC grains is from about 1:1.5 to about 1.5:1, where the mass ratio of primary TiC grains to secondary TiC grains is the mass of the primary TiC grains divided by the mass of the secondary TiC grains.