Effect of nitriding pre‐treatment on the tribocorrosion behavior of physical vapor deposition‐coated tool steel

Abstract

Cr‐Al‐Ti‐B‐N hard coating is deposited onto the AISI D2 cold‐worked tool steel by means of a hybrid physical vapor deposition (PVD) technique. The effect of plasma nitriding pre‐treatment on the tribocorrosion behavior of the hard‐coated tool steel is investigated using a ball‐on‐disc sliding wear tribometer equipped with an electrochemical testing set up. Tribocorrosive characteristics are analyzed by optical and scanning electron microscopy, 3D surface profilometry, and open circuit potential (OCP) measurement. The coefficient of friction and OCP varies depending on the degree of damage to the hard coating, such that the point at which the substrate is first exposed can be identified by these measurements. The plasma nitriding pretreatment increases the surface hardness significantly and, therefore, the adhesion of the PVD hard coating to the substrate material. As a consequence, the material's wear resistance is enhanced and its durability against tribocorrosion is improved.

Exploring the Interplay between Tribocorrosion and Surface Chemistry of the ASTM F139 Surgical Stainless Steel in Phosphate-Buffered Saline Solution

“…The dry sliding condition exhibited the highest COF values, reaching approximately 0.25 at the end of the test. The COF values were lower for the specimens subjected to the tribocorrosion tests, due to the well-known lubricating action of the electrolyte, as reported by several authors [30][31][32]. The COF value of the OCP condition is higher than the…”