The formation of diamond-like carbon structure anchored in the nitrided layer of M50 steel during plasma-assisted thermochemical treatment

Abstract18Ni-300 maraging steel manufactured by selective laser melting was plasma nitrided to improve its wear and corrosion resistance. The effects of a prior solution treatment, aging and the combination of both on the microstructure and the properties after nitriding were investigated. The results were compared with conventionally produced 18Ni-300 counterparts subjected to the same heat- and thermo-chemical treatments. The plasma nitriding was performed under the same conditions (temperature of 520 °C and time of 6 h) as the aging in order to investigate whether the nitriding and the aging could be carried out simultaneously in a single step. The aim of this work was to provide a better understanding of the morphology and chemical composition of the nitrided layer in the additive-manufactured maraging steel as a function of the prior heat treatments and to compare the wear and corrosion resistance with those of conventional maraging steel. The results show that nitriding without any prior aging leads to cracks in the compound layer, while nitriding of the prior-heat-treated additive-manufactured maraging steel leads to benefits from the thermochemical treatment in terms of wear and corrosion resistance. Some explanations for the origins of the cracks and pores in the nitride layers are provided.

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Islet Nitriding of Product Surfaces Made from Alloy Steel

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.265.215 ◽

2017 ◽

Vol 265 ◽

pp. 215-220 ◽

Cited By ~ 1

Author(s):

N.K. Krioni ◽

A.A. Mingazheva ◽

A.Y. Kononova ◽

A.D. Mingazhev ◽

V.A. Gafarova

Keyword(s):

Wear Resistance ◽

Surface Layer ◽

New Technologies ◽

Nitrided Layer ◽

Composite Layer ◽

Thermochemical Treatment ◽

High Wear Resistance ◽

Thermochemical Method ◽

Machine Parts ◽

Modern Machine

One of the most urgent problems of modern machine engineering is to increase the wear resistance of machine parts. The appearance of new technologies of parts strengthening treatment and improvement of the existing ones, especially the technologies based on thermochemical method, remain quite sought-after and are successfully used to improve the operational properties of the parts. Parts surface layer nitriding as the most common method of improving the service life and reliability of the modern machine parts got a new quality due to the use of ion-plasma processes. At the same time, the ever-increasing requirements for performance of machines and devices of different purposes, intensification and tightening of the conditions for their operation requires the creation of new nitriding technologies to provide a range of required properties of parts surface materials. This article is dedicated to the development and research of new nitriding technologies for alloyed steel parts. The aim of the proposed nitriding technology is to provide a composite layer combining high wear resistance and ductility of surface layer material. A feature of the nitriding technology is creating the conditions of processes of thermochemical treatment of parts, making it possible to form the islet nitrided layer.

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STUDY OF PLASMA ION NITRIDING OF AISI H13 STEEL

Revista de Engenharia Térmica ◽

10.5380/reterm.v19i2.78613 ◽

2020 ◽

Vol 19 (2) ◽

pp. 46

Author(s):

M. C. L. Souza ◽

G. R. da Silva ◽

E. S. Souza ◽

W. C. L. Pinto ◽

N. C. O. Tapanes

Keyword(s):

Nitrided Layer ◽

Cutting Tools ◽

Surface Hardness ◽

Gaseous Mixture ◽

Thermochemical Treatment ◽

Ion Nitriding ◽

H13 Steel ◽

Aisi H13 Steel ◽

Aisi H13 ◽

Work Samples

This work studied the thermochemical treatment of AISI H13 steel used for extrusion of aluminum parts, by plasma ionic nitriding, with the objective of increasing the surface hardness of the mold, by forming an external layer of stable nitrides, increasing the resistance to wear, fatigue, corrosion and thermal resistance. Because it uses ions, plasma ion nitriding is more efficient than liquid and gas nitriding. This process is widely used for ferrous materials and aluminum. The main applications are for extrusion, material injection molds, cutting tools and automotive parts. In this work, samples of the AISI H13 steel were nitrided to be used as aluminum injection molds. The treatment was carried out at 300 oC in a sodium cyanide bath, for a period of 6 h at a pressure of 15 mTorr (2 Pa). The gaseous mixture inside the nitreter consisted of 80% N2 + 20% H2. After treatment, Vickers hardness measurements reached surface values of 963 HV. The results at the end of the treatment showed a 122 µm nitrided layer.

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Possibilities of Additive Technologies for the Manufacturing of Tooling from Corrosion-Resistant Steels in Order to Protect Parts Surfaces from Thermochemical Treatment

Metals ◽

10.3390/met11101551 ◽

2021 ◽

Vol 11 (10) ◽

pp. 1551

Author(s):

Alexander Metel ◽

Tatiana Tarasova ◽

Evgenii Gutsaliuk ◽

Roman Khmyrov ◽

Sergei Egorov ◽

...

Keyword(s):

Mechanical Properties ◽

Plasma Nitriding ◽

Nitrided Layer ◽

Linear Thermal Expansion ◽

Thermochemical Treatment ◽

Spheroidal Graphite ◽

Corrosion Resistant ◽

Ion Plasma ◽

Composition And Structure ◽

Stage 1

The structure and physical–mechanical properties of products made from powders of corrosion-resistant steel 12X18H10T by the laser-beam powder bed fusion (LB-PBF) and subsequent ion-plasma nitriding in the work were investigated. Comparative studies of the physical mechanical properties of specimens made by the LB-PBF and conventional method from steel of the same grade were carried out. The density of the specimens and the coefficient of linear thermal expansion (CLTE) after the LB-PBF are almost the same as those of the conventionally manufactured specimens. Our analysis of the obtained dilatograms in the temperature range from 20 to 600 °C showed that the CLTE of steel after the LB-PBF is within acceptable limits (18.6 × 10−6 1/°C). Their hardness, tensile strength, yield strength and elongation are higher than those of a conventionally manufactured specimen. The phase composition and structure of specimens of steel 12X18H10T made by the LB-PBF after the process of ion-plasma nitriding were investigated. The obtained results show that the mode of ion-plasma nitriding used in this case (stage 1—570 °C for 36 h; stage 2—540 °C for 12 h) does not lead to deterioration of the characteristics of the selected steel. A technological process for the manufacture of modified tooling from 12X18H10T steel by the LB-PBF was developed. It protects the surfaces that are not subject to nitriding and makes it possible to obtain a uniform high-quality nitrided layer on the working surface of the part made from spheroidal graphite iron.

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Structural Development of Expanded Austenite on Duplex Stainless Steel by Low Temperature Thermochemical Nitriding Process

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.576.260 ◽

2012 ◽

Vol 576 ◽

pp. 260-263 ◽

Cited By ~ 5

Author(s):

L.H. Paijan ◽

M.N. Berhan ◽

M.S. Adenan ◽

N.F.M. Yusof ◽

E. Haruman

Keyword(s):

Stainless Steel ◽

Duplex Stainless Steel ◽

Layer Structure ◽

Nitrided Layer ◽

Thermochemical Treatment ◽

Structural Development ◽

Corrosion Properties ◽

Temperature Range ◽

Hardness Tester ◽

Expanded Austenite

This paper describes the results of gaseous thermochemical treatment of nitriding duplex stainless steel using tube furnace. The nitriding was performed in temperature range between 400°C and 500°C for 6 hours, forming a dual layer structure with hard nitrogen layer. The nitriding gas composition used for this process is 50% NH4 + 50% N2 and 25% NH4 + 75% N2. The structural development was characterised using hardness tester, X-ray diffraction (XRD) and scanning electron microscopy (SEM). Based on the experimental results, it was found that nitrided layer produced maximum thickness nitrided layer about 13.96µm and hardness 666.3 HV0.025 at 450°C with 50% NH4. The formation of expanded austenite was observed in temperature range between 400°C and 500°C. However, the cromium nitride has been developed at temperature 500°C which decreased the corrosion properties of duplex stainless steel.

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Use of Plasma Nitriding to Improve the Wear and Corrosion Resistance of 18Ni-300 Maraging Steel Manufactured by Selective Laser Melting

10.21203/rs.3.rs-119456/v1 ◽

2020 ◽

Author(s):

Matjaž Godec ◽

Bojan Podgornik ◽

Aleksandra Kocijan ◽

Črtomir Donik ◽

Danijela Skobir Balantič

Keyword(s):

Corrosion Resistance ◽

Maraging Steel ◽

Selective Laser Melting ◽

Plasma Nitriding ◽

Nitrided Layer ◽

Solution Treatment ◽

Thermochemical Treatment ◽

Laser Melting ◽

Wear And Corrosion ◽

Wear And Corrosion Resistance

Abstract 18Ni-300 maraging steel manufactured by selective laser melting was plasma nitrided to improve its wear and corrosion resistance. The effects of a prior solution treatment, aging and the combination of both on the microstructure and the properties after nitriding were investigated. The results were compared with conventionally produced 18Ni-300 counterparts subjected to the same heat- and thermo-chemical treatments. The plasma nitriding was performed under the same conditions (temperature of 520 °C and time of 6 hours) as the aging in order to investigate whether the nitriding and the aging could be carried out simultaneously in a single step. The aim of this work was to provide a better understanding of the morphology and chemical composition of the nitrided layer in the additive-manufactured maraging steel as a function of the prior heat treatments and to compare the wear and corrosion resistance with those of conventional maraging steel. The results show that nitriding without any prior aging leads to cracks in the compound layer, while nitriding of the prior-heat-treated additive-manufactured maraging steel leads to benefits from the thermochemical treatment in terms of wear and corrosion resistance. Some explanations for the origins of the cracks and pores in the nitride layers are provided.

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