Influence of Nitrogen Content on the Corrosion Behavior of Powder Metallurgy Nickel‐Free Austenitic Stainless Steel

Abstract

Herein, powder metallurgy gas-solid nitriding was used to prepare a high-nitrogen Ni-free austenitic stainless steel with more than 1.0 wt.% N. Study of the microstructures and corrosion resistances of the as-prepared samples revealed that the corrosion weight loss, size, number of corrosion pits, and corrosion depth decreased as the N content increased from 1.19 to 1.37 wt.%. The self-corrosion current densities of the alloys were determined from their potentiodynamic polarization curves. The changes in the capacitive arc radius as demonstrated by the Nyquist curves were consistent with the conclusions of the immersion corrosion analysis; that is, a high N content leads to a high corrosion resistance.

Effect of Cu-Sn Addition on Corrosion Property of Pressureless Sintered Fe-Cu-Co Substrate Alloys

“…The liquid phase should disappear in the later stage, making it difficult to shrink the pore and further improve the density. It can be seen from Figure 1 that the sintering pores have irregular shapes, which are completely different from some round type pores formed in alloys by high temperature solid phase sintering [ 37 , 38 ]. This is because the alloys are mainly composed of α-Fe phase grains, and the high density of powder metallurgical steel should be sintered at a temperature higher than 1120 °C [ 39 , 40 ].…”

“…When the addition of Cu-Sn is 14 wt.%, the corrosion current density is only 4.30 × 10 −6 A/cm 2 . According to Faraday’s law, the higher corrosion current density of an alloy means a faster corrosion rate, and worse corrosion resistance [ 38 , 41 ]. With the increase in Cu-Sn content, the corrosion current density of the alloy decreases, indicating that the addition of Cu-Sn to Fe-Cu-Co can improve the corrosion resistance of the substrate.…”

Bioactivity, Cytotoxicity, and Tribological Studies of Nickel-Free Austenitic Stainless Steel Obtained via Powder Metallurgy Route

“…The average FC value and wear rate from the experiments are shown in Fig- Comparing the presented results with the literature data, it can be concluded that the material obtained in this work has very promising corrosion resistance. Yu et al [26], investigating the effect of nitrogen content on the corrosion properties of stainless steel, showed that a higher nitrogen content improves corrosion resistance. In the material with the chemical composition Fe-17Cr-11Mn-3-Mo-1.2N (in wt.…”

The efficiency of removing heavy metal ions from industrial electropolishing wastewater using natural materials

“…One of the techniques used to treat stainless steels is electropolishing [10][11][12][13][14] . This process is designed to change the surface properties of an object in order to improve its aesthetic value by smoothing and making the surface glossy and at the same time increasing its corrosion resistance 12,[15][16][17][18][19] . This method has many applications including food, automotive, and medical industries [20][21][22] .…”