Examination of the influence of heat treatment on the corrosion resistance of martensitic stainless steels

Abstract

Martensitic stainless steels are commonly used in cutlery fabrication requiring high hardness and sufficient corrosion resistance. The heat treatment process affects the mechanical and electrochemical behavior of martensitic stainless steels due to the precipitation of chromium carbides. Depending on the heat treatment the corrosion resistance of these steels can vary strongly, and improper heat treatment parameters can lead to a weak pitting corrosion resistance. The aim of this work is to identify heat treatment parameters influencing the corrosion resistance of martensitic stainless steels by using three different electrochemical testing methods. To this purpose, five different heat treatments were applied to the alloys 1.4116 and 1.4034. In addition to the determination of the critical pitting potentials and the modified double-loop electrochemical potentiodynamic reactivation tests (DL-EPR) a new KorroPad indicator test was used assessing the pitting corrosion behavior. The results showed that all methods used were in good agreement for verifying the influence of the various heat treatment parameters on the corrosion behavior and to identify the effect of heat treatment conditions on the pitting corrosion resistance.

Investigations proofing the passive layer stability of stainless steels

“…The presented investigations and the many practical applications the KorroPad technique proved to be excellently suitable for describing the passive layer stability. Compared to other established methods to describe the corrosion resistance like salt spray and electrochemical tests the short testing time and the non‐destructive type of the KorroPad test are advantageous.…”

Dynamics of Tempering Processes in Stainless Steel

“…Rosemann et al performed Thermocalc calculation for carbide composition which shows at 500 °C that 10% of the mass in carbides is replaced by Fe at the expense of Cr. A Cr depleted zone at the interface between the carbides and matrix was present and insufficient chromium content in the metal matrix leads to unstable formation of a passive layer and therefore a weak resistance to local corrosion [4]. Therefore, the relationship between temperature and carbide composition dictates the corrosion resistance as a function of the applied heat treatment.…”

“…The oxidation process at the surface is in particular relevant for the corrosion resistance of stainless steel [2]- [4]. Several high temperature experimental methods exist to explore the mechanisms behind surface oxidation.…”

Influence of austenitizing and tempering on the corrosion behavior and sensitization of martensitic stainless steel X50CrMoV15

“…Their corrosion resistance is based on their chromium content of 13–15 wt% leading to passive layer formation on the steel surface, depending, among other parameters, on the pH value of the surrounding solution . Heat treatment influences mechanical properties and the corrosion behavior of martensitic stainless steels significantly . The influence of heat treatment on the corrosion behavior even exceeds the influence of alloy composition and surface treatment and is therefore most important when evaluating the corrosion resistance of martensitic stainless steels .…”

“…Heat treatment influences mechanical properties and the corrosion behavior of martensitic stainless steels significantly . The influence of heat treatment on the corrosion behavior even exceeds the influence of alloy composition and surface treatment and is therefore most important when evaluating the corrosion resistance of martensitic stainless steels . High corrosion resistance and hardness require an optimal heat treatment procedure.…”