Wear behaviour of martensitic stainless steel after PIII surface treatment

Martensitic stainless steel samples-1.4021 (X20Cr13), 1.4034 (X46Cr13), 1.4057 (X17CrNi16.2), 1.4104 (X14CrMoS17) and 1.4542(X5CrNiCuNb17.4)-were implanted with nitrogen using plasma immersion ion implantation (PIII) at different temperatures between 320 and 380 °C and at different pulse voltages for up to 3 h. The formation of an expanded martensite layer was found after implantation for all samples with a surface martens hardness of up to 10,000 N/mm2. The wear was measured in a dry ball-on-disc configuration. The specific wear was reduced by a factor of 2-10 to the same absolute level as for expanded austenite. With increasing contact pressure, an increased wear rate was found, while no influence of the speed was observed.