There are provided a precipitation strengthening type martensitic steel having both a tensile strength of a 1500 MPa class and a high Charpy absorption energy of 30 J or higher, and a manufacturing process thereof. The precipitation strengthening type martensitic steel includes, in terms of mass %, 0.05% or less of C, 0.2% or less of Si, 0.4% or less of Mn, 7.5 to 11.0% of Ni, 10.5 to 13.5% of Cr, 1.75 to 2.5% of Mo, 0.9 to 2.0% of Al, less than 0.1% of Ti, and a remainder of Fe and impurities, and contains 0.1 to 6.0% of austenite in terms of a volume fraction.

There are provided a precipitation strengthening type martensitic steel having both a tensile strength of a 1500 MPa class and a high Charpy absorption energy of 30 J or higher, and a manufacturing process thereof. The precipitation strengthening type martensitic steel includes, in terms of mass %, 0.05% or less of C, 0.2% or less of Si, 0.4% or less of Mn, 7.5 to 11.0% of Ni, 10.5 to 13.5% of Cr, 1.75 to 2.5% of Mo, 0.9 to 2.0% of Al, less than 0.1% of Ti, and a remainder of Fe and impurities, and contains 0.1 to 6.0% of austenite in terms of a volume fraction.

The present invention is to provide a method for manufacturing a martensite-based precipitation strengthening stainless steel, which effectively enables crystal grains to become finer by improving a solution treatment method. The method for manufacturing a martensite-based precipitation strengthening stainless steel containing 0.01 to 0.05 mass % of C, 0.2 mass % or less of Si, 0.4 mass % or less of Mn, 7.5 to 11.0 mass % of Ni, 10.5 to 14.5 mass % of Cr, 1.75 to 2.50 mass % of Mo, 0.9 to 2.0 mass % of Al, less than 0.2 mass % of Ti, and Fe and impurities as a remainder, which is provided by the present invention, includes performing a solid solution treatment at 845 to 895° C. once or more.

A nanocrystalline bainitic steel consisting of, by weight percentage: 0.3% to 0.6% carbon; 9.0% to 20.0% nickel; up to 10% cobalt; 1.0% to 4.5% aluminium; up to 0.5% molybdenum; up to 0.5% manganese; up to 0.5% tungsten; up to 3.0% chromium; and the balance being iron and impurities.

An optimized Gamma-prime (γ′) strengthened austenitic transformation induced plasticity (TRIP) steel comprises a composition designed and processed such that the optimized γ′ strengthened austenitic TRIP steel meets property objectives comprising a yield strength of 896 MPa (130 ksi), and an austenite stability designed to have M.sub.s.sup.σ(sh)=−40° C., wherein M.sub.s.sup.σ(sh) is a temperature for shear, and wherein the property objectives are design specifications of the optimized γ′ strengthened austenitic TRIP steel. The optimized γ′ strengthened austenitic TRIP steel is Blastalloy TRIP 130.

An optimized Gamma-prime (γ′) strengthened austenitic transformation induced plasticity (TRIP) steel comprises a composition designed and processed such that the optimized γ′ strengthened austenitic TRIP steel meets property objectives comprising a yield strength of 896 MPa (130 ksi), and an austenite stability designed to have M.sub.s.sup.σ(sh)=−40° C., wherein M.sub.s.sup.σ(sh) is a temperature for shear, and wherein the property objectives are design specifications of the optimized γ′ strengthened austenitic TRIP steel. The optimized γ′ strengthened austenitic TRIP steel is Blastalloy TRIP 130.

An end block is disclosed. The end block may include a body extending between a front side, a back side, a left side, a right side, a top side and a bottom side. Furthermore, the body may include a first bore extending through the body between an inlet port and an outlet port and a cylinder bore extending between a cylinder port and the first bore. Moreover, the body may include a precipitation hardened martensitic stainless steel comprising between 0.08% and 0.18% by weight carbon, between 10.50% and 14.00% by weight chromium, between 0.65% and 1.15% by weight nickel, between 0.85% and 1.30% by weight copper, iron, and a first precipitate comprising the copper.

An end block is disclosed. The end block may include a body extending between a front side, a back side, a left side, a right side, a top side and a bottom side. Furthermore, the body may include a first bore extending through the body between an inlet port and an outlet port and a cylinder bore extending between a cylinder port and the first bore. Moreover, the body may include a precipitation hardened martensitic stainless steel comprising between 0.08% and 0.18% by weight carbon, between 10.50% and 14.00% by weight chromium, between 0.65% and 1.15% by weight nickel, between 0.85% and 1.30% by weight copper, iron, and a first precipitate comprising the copper.

The invention relates to a cold work tool steel. The steel comprises the following main components (in wt. %): C 0.5-2, N 1.3-3, Si 0.05-1.2, Mn 0.05-1, Cr 2.5-5.5, Mo 0.8-2.2, V 6-18, with a balance of optional elements, iron, and impurities.

An aspect of the present disclosure relates to a high-strength steel material having enhanced resistance to crack initiation and propagation at low temperature.