Precipitation hardening stainless steel and its manufacture

A precipitation hardening stainless steel, said stainless steel comprising in wt %:

• C:
• 0.05-0.30 wt %
• Mo:
• 0.5-1.5 wt %
• Al:
• 1.8-3 wt %
• V:
• 0.25-1.5 wt %
• Co:
• 0-0.03 wt %
• Mn:
• 0-0.5 wt %
• Si:
• 0-0.3 wt %
• Ni:
• ≥9 wt % and <10 wt %
• Cr:
• 10.5-13 wt %
• wherein impurities of nitrogen, oxygen, and sulfur are limited to 30 ppm each,
• remaining part up to 100 wt % is Fe, and impurity elements,
• wherein the steel comprises more than or equal to 80 wt % of a martensitic phase, with the remaining part made up of mainly an austenitic phase, wherein the composition of said stainless steel is within an area formed in a Schaeffler diagram, which diagram is based on the following equations:
• Creq=Cr+Mo+1.5*Si+0.5*Nb in wt % on the x-axis
• Nieq=Ni+30*C+0.5*Mn in wt % on the y-axis
• wherein the area in the Schaeffler diagram is defined by 11≤Creq≤15.4 and 10.5≤Nieq≤15 in wt %,
• with the additional proviso that the amounts of Al and Ni also fulfil a formula Al=(Ni/4)±0.5 in wt %, and with the proviso that the amount of Al is 1.8 wt % if the formula results in an amount of Al lower than 1.8 wt % and that the amount of Al is 3 wt % if the formula results in an amount of Al exceeding 3 wt %.