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T Bell - One of the best experts on this subject based on the ideXlab platform.
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a comparative study of low temperature plasma nitriding carburising and nitrocarburising of aisi 410 Martensitic Stainless Steel
Materials Science and Technology, 2007Co-Authors: C X Li, T BellAbstract:AbstractSamples of an AISI410 Martensitic Stainless Steel were plasma nitrided (PN), plasma carburised (PC) and plasma nitrocarburised (PCN) at a low temperature of 450°C for 20 h. General metallurgical characterisations were performed to compare the phase constituents, the chemical compositions, the microstructures and hardness of the untreated and various plasma treated surfaces. Pin on disc tests and polarisation corrosion tests were performed to evaluate the wear and corrosion properties of the plasma treated and untreated Steel. The results showed that the low temperature plasma treated surfaces of 410 Martensitic Stainless Steel were dominated with compounds of either nitrides (for PN), carbides (for PC) or a mixed structure of carbonitride and carbides (for PCN). Plasma nitriding and nitrocarburising significantly improved the surface hardness, wear resistance and corrosion resistance of the 410 Martensitic Stainless Steel. However, plasma carburising under the present treatment condition only achi...
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corrosion properties of plasma nitrided aisi 410 Martensitic Stainless Steel in 3 5 nacl and 1 hcl aqueous solutions
Corrosion Science, 2006Co-Authors: C X Li, T BellAbstract:Abstract Samples of an AISI 410 Martensitic Stainless Steel were plasma nitrided at a temperature of 420 °C, 460 °C or 500 °C for 20 h. The composition, microstructure and hardness of the nitrided samples were characterised using a variety of analytical techniques. In particular, the corrosion properties of the untreated and plasma nitrided samples were evaluated using anodic polarisation tests in 3.5% NaCl solution and immersion tests in 1% HCl acidic water solution. The results showed that plasma nitriding produced a relatively thick nitrided case consisting of a compound layer and a nitrogen diffusion layer on the 410 Stainless Steel surface. Plasma nitriding not only increased the surface hardness but also improved the corrosion resistance of the Martensitic Stainless Steel. In the immersion test, nitrided samples showed lower weight loss and lower corrosion rate than untreated one. In the electrochemical corrosion tests, the nitrided samples showed higher corrosion potentials, higher pitting potentials and greatly reduced current densities. The improved corrosion resistance was believed to be related to the iron nitride compound layer formed on the Martensitic Stainless Steel surface during plasma nitriding, which protected the underlying metal from corrosive attack under the testing conditions.
Yuntao Xi - One of the best experts on this subject based on the ideXlab platform.
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improvement of corrosion and wear resistances of aisi 420 Martensitic Stainless Steel using plasma nitriding at low temperature
Surface & Coatings Technology, 2008Co-Authors: Yuntao XiAbstract:Abstract The influence of low temperature plasma nitriding on the wear and corrosion resistance of AISI 420 Martensitic Stainless Steel was investigated. Plasma nitriding experiments were carried out with DC-pulsed plasma in 25% N2 + 75% H2 atmosphere at 350 °C, 450 °C and 550 °C for 15 h. The composition, microstructure and hardness of the nitrided samples were examined. The wear resistances of plasma nitrided samples were determined with a ball-on-disc wear tester. The corrosion behaviors of plasma nitrided AISI420 Stainless Steel were evaluated using anodic polarization tests and salt fog spray tests in the simulated industrial environment. The results show that plasma nitriding produces a relatively thick nitrided layer consisting of a compound layer and an adjacent nitrogen diffusion layer on the AISI 420 Stainless Steel surface. Plasma nitriding not only increases the surface hardness but also improves the wear resistance of the Martensitic Stainless Steel. Furthermore, the anti-wear property of the Steel nitrided at 350 °C is much more excellent than that at 550 °C. In addition, the corrosion resistance of AISI420 Martensitic Stainless Steel is considerably improved by 350 °C low temperature plasma nitriding. The improved corrosion resistance is considered to be related to the combined effect of the solid solution of Cr and the high chemical stable phases of ɛ-Fe3N and αN formed on the Martensitic Stainless Steel surface during 350 °C low temperature plasma nitriding. However, plasma nitriding carried out at 450 °C or 550 °C reduces the corrosion resistance of samples, because of the formation of CrN and leading to the depletion of Cr in the solid solution phase of the nitrided layer.
S V Subramanian - One of the best experts on this subject based on the ideXlab platform.
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effect of n on microstructure and mechanical properties of 16cr5ni1mo Martensitic Stainless Steel
Materials & Design, 2012Co-Authors: X P, Luda Wang, S V SubramanianAbstract:Abstract The effect of adding N (about 0.1% in mass) to low carbon 16Cr5Ni1Mo Martensitic Stainless Steel by adding nitride ferroalloy under argon protective atmospheric of near normal pressure on phase transformation and microstructure of Steels subjected to normalizing and tempering was investigated by using dilatometer, laser scanning confocal microscopy, transmission electron microscopy and X-ray diffraction, and its consequence on mechanical properties was evaluated by tensile and impact tests. N can effectively avoid the occurrence of δ ferrite during solidification. N retards the kinetics of the formation of reversed austenite and promotes the occurrence of Cr2N during tempering above 550 °C. The strength properties of the Steel as normalized is enhanced by N alloying without much decrease in elongation and toughness due to the combined effects of N solution strengthening, suppression of δ ferrite and retained austenite. The slight influence of N addition on mechanical properties of Martensitic Stainless Steel after tempering above 550 °C is attributed to the precipitation of coarse rod-like Cr2N and loss of coherence. While the increase in volume fraction of retained austenite originated from reversed austenite with tempering temperature contributes to the decrease in strength properties and increase in toughness and elongation, the retransformation of reversed austenite into martensite affects these properties inversely.
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role of nb in low interstitial 13cr super Martensitic Stainless Steel
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2011Co-Authors: X P, Lin Wang, S V SubramanianAbstract:Abstract The effect of adding 0.1 wt% Nb to low interstitial (N 0.01 wt%, C 0.01 wt%) 13Cr super Martensitic Stainless Steel (SMSS) on solid phase transformation and microstructures achieved by normalizing and tempering was investigated using dilatometer, electron backscattered diffraction (EBSD), transmission electron microscope (TEM), X-ray diffraction (XRD), and its consequence on mechanical properties was examined to clarify the role of Nb in low interstitial Martensitic Stainless Steel. Nb was found to retard kinetics of reversed austenite formation during tempering and to suppress the occurrence of Cr rich precipitates. The measurement of mechanical properties shows that while the strength properties were significantly increased by nano-scale precipitates enriched in Nb in the Steel with 0.10 wt% Nb, the ductility and toughness properties were restored by optimum volume fraction of retained austenite. Excellent strength and adequate toughness properties were obtained by tempering the Steel with 0.10 wt% Nb and low interstitial (N 0.01 wt%, C 0.01 wt%) Steel at 600 °C.
C X Li - One of the best experts on this subject based on the ideXlab platform.
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a comparative study of low temperature plasma nitriding carburising and nitrocarburising of aisi 410 Martensitic Stainless Steel
Materials Science and Technology, 2007Co-Authors: C X Li, T BellAbstract:AbstractSamples of an AISI410 Martensitic Stainless Steel were plasma nitrided (PN), plasma carburised (PC) and plasma nitrocarburised (PCN) at a low temperature of 450°C for 20 h. General metallurgical characterisations were performed to compare the phase constituents, the chemical compositions, the microstructures and hardness of the untreated and various plasma treated surfaces. Pin on disc tests and polarisation corrosion tests were performed to evaluate the wear and corrosion properties of the plasma treated and untreated Steel. The results showed that the low temperature plasma treated surfaces of 410 Martensitic Stainless Steel were dominated with compounds of either nitrides (for PN), carbides (for PC) or a mixed structure of carbonitride and carbides (for PCN). Plasma nitriding and nitrocarburising significantly improved the surface hardness, wear resistance and corrosion resistance of the 410 Martensitic Stainless Steel. However, plasma carburising under the present treatment condition only achi...
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corrosion properties of plasma nitrided aisi 410 Martensitic Stainless Steel in 3 5 nacl and 1 hcl aqueous solutions
Corrosion Science, 2006Co-Authors: C X Li, T BellAbstract:Abstract Samples of an AISI 410 Martensitic Stainless Steel were plasma nitrided at a temperature of 420 °C, 460 °C or 500 °C for 20 h. The composition, microstructure and hardness of the nitrided samples were characterised using a variety of analytical techniques. In particular, the corrosion properties of the untreated and plasma nitrided samples were evaluated using anodic polarisation tests in 3.5% NaCl solution and immersion tests in 1% HCl acidic water solution. The results showed that plasma nitriding produced a relatively thick nitrided case consisting of a compound layer and a nitrogen diffusion layer on the 410 Stainless Steel surface. Plasma nitriding not only increased the surface hardness but also improved the corrosion resistance of the Martensitic Stainless Steel. In the immersion test, nitrided samples showed lower weight loss and lower corrosion rate than untreated one. In the electrochemical corrosion tests, the nitrided samples showed higher corrosion potentials, higher pitting potentials and greatly reduced current densities. The improved corrosion resistance was believed to be related to the iron nitride compound layer formed on the Martensitic Stainless Steel surface during plasma nitriding, which protected the underlying metal from corrosive attack under the testing conditions.
Kunyu Zhao - One of the best experts on this subject based on the ideXlab platform.
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Synergistic effect of Cu and Ni on the formation of reversed austenite in super Martensitic Stainless Steel
Ironmaking & Steelmaking, 2018Co-Authors: Dong Ye, Wen Jiang, Kunyu Zhao, Lihua Yu, Jie SuAbstract:ABSTRACTThe interplay of Cu and Ni on the formation of reversed austenite in super Martensitic Stainless Steel (SMSS) was discussed in this study. Ni concentration in reversed austenite increases f...
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Reverse Transformation Mechanism of Martensite to Austenite in 00Cr15Ni7Mo2WCu2 Super Martensitic Stainless Steel
Steel Research International, 2014Co-Authors: Wen Jiang, Dong Ye, Jie Su, Jun Li, Kunyu ZhaoAbstract:The reverse transformation mechanism of martensite to austenite in 00Cr15Ni7Mo2WCu2 super Martensitic Stainless Steel has been studied. The experimental results indicated that the volume fraction of reversed austenite in 00Cr15Ni7Mo2WCu2 super Martensitic Stainless Steel increased first and then decreased with increasing tempering temperature over a range of 550–750 °C after quenching at 1050 °C. The reversed austenite formed along the martensite lath boundaries. When the tempering temperature was below 700 °C, the reversed austenite grew with a Ni-enrichment; when the temperature was above 700 °C, the reversed austenite re-dissolved and transformed to martensite and a part of the reversed austenite divided the original wider Martensitic laths into a number of thinner ones. The basic mechanism for formation of the reversed austenite is diffusion in 00Cr15Ni7Mo2WCu2 super Martensitic Stainless Steel.
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effect of cu addition on microstructure and mechanical properties of 15 cr super Martensitic Stainless Steel
Materials & Design, 2012Co-Authors: Dong Ye, Wen Jiang, Jie Su, Jun Li, Kunyu ZhaoAbstract:Abstract The effect of adding different content of Cu (0 wt.%, 1.5 wt.% and 3 wt.%) to the 15%Cr super Martensitic Stainless Steel (SMSS) was investigated using optical microscope, scanning electron microscope (SEM), transmission electron microscope (TEM) and X-ray diffraction (XRD). Its consequence on mechanical properties was examined to clarify the role of Cu in the tested Steels. The experimental results indicate that the microstructures of three tested Steels are tempered martensite, retained austenite and reversed austenite; two kinds of austenites are dispersedly distributed among martensite matrix. Cu can solute in matrix under quenching condition and can precipitate as Cu-rich nanometer phase (e-Cu) during tempering. Cu is helpful for the grain refinement and to promote the formation of reversed austenite during tempering. The maximum volume fraction of austenite is 55.9% in the Steel with 3 wt.% Cu, which is responsible for the improvement of ductility. The results of the mechanical properties tests reveal that the mechanical properties are significantly influenced by the volume fraction of austenite. Cu can cause solid solution strengthening, precipitation strengthening and grain refinement strengthening in SMSS. Cu alloyed super Martensitic Stainless Steel exhibits greatly improved mechanical properties.