Precipitation hardening stainless steel is a stainless steel whose matrix is austenitic or martensitic and whose hardness and strength are improved by aging treatment. It contains high levels of chromium, nickel and alloying elements such as molybdenum, titanium and aluminium, and has excellent corrosion resistance, high strength and good machinability. This material is widely used in medical and surgical instruments, where its high strength, corrosion resistance and toughness ensure the safety and effectiveness of the instruments.