scholarly journals Boron Diffusion During Carbon Steel Boriding

2021 ◽  
pp. 64-67
Author(s):  
E.P. Shevchuk ◽  
V.A. Plotnikov ◽  
G.S. Bektasova
Keyword(s):  
Carbon Steel ◽  
Thermal Treatment ◽  
Diffusion Zone ◽  
High Hardness ◽  
High Rate ◽  
Induction Treatment ◽  
Boron Diffusion ◽  
Zone Formation ◽  
Diffusion Layers ◽  
Diffusion Boriding

Protective boride coatings are obtained by chemical-thermal treatment of powder mixtures during induction furnace heating and micro-arc chemical-thermal treatment. Their usage can significantly increase the reliability and durability of steel products. The calculated composition of the saturating charge and the welding flux used to boride steel 20 samples demonstrates that obtained boride diffusion coatings are characterized by high hardness and an extensive diffusion zone. The most optimal composition of the charge that contains iron and boric acid is found to be in the proportion of Fe-25%+H3BO3-75 %. The analysis of the distribution of microhardness over the cross section of coated samples is carried out. The comparative data for the diffusion coefficients and the thickness of the diffusion layers obtained experimentally are presented. The application of the discussed methods makes it possible to intensify the process of diffusion boriding and to ensure the formation of an extensive diffusion zone on the surface of carbon steel products with a high rate of hardening zone formation. The duration of the process is 5 minutes for the induction treatment and 54.05 s for micro-arc chemical-thermal surfacing. It is the main advantage of the experimental techniques mentioned above.

scholarly journals Study of Diffusion Boride Bayers of Steel 20, Obtained by the Micro-Arc Surface

2020 ◽  
pp. 59-63
Author(s):  
E.P. Shevchuk ◽  
V.A. Plotnikov ◽  
G.S. Bektasova
Keyword(s):  
Boric Acid ◽  
Diffusion Zone ◽  
Composite Layer ◽  
High Hardness ◽  
High Strength ◽  
Heterogeneous Structure ◽  
Diffusion Coatings ◽  
The Matrix ◽  
Diffusion Boriding ◽  
Steel 20

We discuss the results of the study of carbon steel 20 boriding performed by the micro-arc chemical-thermal treatment of a mixture containing iron and boric acid. The study has been carried out in scientific laboratories of the EKSU named after S. Amanzholov. It is found out that boride diffusion coatings obtained by this method are characterized by high hardness of 3.5 GPa and have an extensive diffusion zone. The wide diffusion zone is a surface layer of steel in which the compounds of boron and iron are distributed so that a transition region is formed between the hardened region and the matrix. The material of the diffusion zone is a composite consisting of a plastic а-phase of iron and high strength iron borides. X-ray diffraction studies revealed the formation of Fe3B compounds. It is found that the most optimal composition of the mixture contains iron and boric acid in a ratio of 1:3 (Fe-25% + H3BO3-75 %). The use of the micro-arc surfacing method makes it possible to intensify the process of diffusion boriding in comparison with traditional methods. Also, it ensures that a hardened composite layer with a heterogeneous structure formed by the diffusion-crystallization mechanism is developed on a surface of steel products.

Laser Assisted High Entropy Alloy Coating on Low Carbon Steel

2019 ◽  
Vol 813 ◽  
pp. 159-164
Author(s):  
Carlos Alberto Souto ◽  
Gustavo Faria Melo da Silva ◽  
Laura Angelica Ardila Rodriguez ◽  
Aline C. de Oliveira ◽  
Kátia Regina Cardoso
Keyword(s):  
Wear Resistance ◽  
Carbon Steel ◽  
Low Carbon Steel ◽  
High Hardness ◽  
Alloy Coating ◽  
High Entropy Alloy ◽  
Nominal Composition ◽  
Low Carbon ◽  
High Entropy ◽  
Scan Speed

Coatings with high entropy alloys of the AlCoCrFeNiV system were obtained by selective laser melting on low carbon steel substrates. The effect of the variation of the Fe and V contents as well as the laser processing parameters in the development of the coating were evaluated. The coatings were obtained from the simple powder mixtures of the high purity elemental components in a planetary ball mill. The coatings were obtained by using CO2 laser with a power of 100 W, diameter of 0.16 mm, and scan speed varying from 3 to 12 mm/s. Phase constituents, microstructure and hardness were investigated by XRD, SEM, and microhardness tester, respectively. Wear resistance measurements were carried out by the micro-abrasion method using ball-cratering tests. The coatings presented good adhesion to the substrate and high hardness, of the order of 480 to 650 HV. Most homogeneous coating with nominal composition was obtained by using the higher scan speed, 12 mm/s. Vanadium addition increased hardness and gave rise to a high entropy alloy coating composed by BCC solid solutions. Ball cratering tests conducted on HEA layer showing improvement of material wear resistance, when compared to base substrate, decreasing up to 88% its wear rate, from 1.91x10-6 mm3/Nmm to 0.23x10-6 mm3/Nmm.

Increasing Hardness of Surface Layer of Low-Carbon Steel by Account of Plasma Treatment of Coating Modification

2021 ◽  
Vol 316 ◽  
pp. 794-802
Author(s):  
Andrey E. Balanovsky ◽  
Van Trieu Nguyen
Keyword(s):  
Surface Layer ◽  
Thermal Treatment ◽  
Plasma Treatment ◽  
Plasma Heating ◽  
High Surface ◽  
Surface Hardness ◽  
High Hardness ◽  
Diffusion Region ◽  
Low Carbon ◽  
Wide Range

The Purpose of paper is to conduct studies to assess the possibility of increasing the hardness of the surface layer of steel St3 grade by plasma heating of the applied surface coating containing powder alloy PR-N80X13S2R. Mixtures of pasta were divided into 2 groups: for furnace chemical-thermal treatment and plasma surface melting. The study of the microstructure showed a difference in the depth of the saturated layer, depending on the processing method, during chemical-thermal treatment-1 mm, plasma fusion - 2 mm. The results of measuring the surface micro-hardness showed that, the obtained coating from a mixture of PR-N80X13S2R + Cr2O3 + NH4Cl has a uniform high surface hardness (31-64 HRC), from a mixture of only PR-N80X13S2R - the surface hardness varies in a wide range (15-60 HRC). The study of the microhardness of the cross section of the surface layer showed that, the diffusion region: from a mixture of powder PR-N80X13S2R + Cr2O3 + NH4Cl has uniform hardness (450-490 HV); from a mixture of PR-N80X13S2R - hardness increases in the depth of the molten region (from 300 to 600 HV), and sharply decreases in the heat affected zone (210-170 HV). The use of PR-N80X13S2R alloy powder as the main component in the composition of the paste deposited on the St3 surface during plasma treatment leads to the formation of a doped surface layer with high hardness.

Fatigue Crack Growth Behavior of High Carbon Steel (SM53C) by Using Induction Hardening

2008 ◽  
Author(s):  
Hyun Bae Jeon ◽  
Tae Hoon Song ◽  
Sung Ho Park ◽  
Sun Chul Huh ◽  
Won Jo Park
Keyword(s):  
Fatigue Crack ◽  
Carbon Steel ◽  
Fatigue Crack Growth ◽  
Crack Growth ◽  
High Frequency ◽  
High Carbon Steel ◽  
Induction Treatment ◽  
Special Focus ◽  
High Carbon ◽  
High Frequency Induction

Recently, with the high performance and efficiency of machine, there have been required the multi-functions in various machine parts, such as the heat resistance, the abrasion resistance and the stress resistance as well as the strength. Fatigue crack growth tests were carried out to investigate the fatigue characteristics of high carbon steel (SM53C) experienced by high-frequency induction treatment. The influence of high-frequency induction treatment on fatigue limit was experimentally examined with the special focus on the variation of surface microstructure and the fatigue crack initiation and propagation through fractography. Also, the shape of hardening depth, hardened structure, hardness, and fatigue-fracture characteristics of SM53C composed by carbon steel are also investigated.

scholarly journals Carbonitration of a Tool for Pressing Stainless Steel Pipes

2020 ◽  
Vol 7 (2) ◽  
pp. C17-C21
Author(s):  
I. V. Ivanov ◽  
M. V. Mohylenets ◽  
K. A. Dumenko ◽  
L. Kryvchyk ◽  
T. S. Khokhlova ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Thermal Treatment ◽  
Heat Resistance ◽  
Alkali Metals ◽  
Matrix Ring ◽  
High Hardness ◽  
Operating Conditions ◽  
Matrix Rings ◽  
Conventional Heat Treatment ◽  
The Stability

To upgrade the operational stability of the tool at LLC “Karbaz”, Sumy, Ukraine, carbonation of tools and samples for research in melts of salts of cyanates and carbonates of alkali metals at 570–580 °C was carried out to obtain a layer thickness of 0.15–0.25 mm and a hardness of 1000–1150 НV. Tests of the tool in real operating conditions were carried out at the press station at LLC “VO Oscar”, Dnipro, Ukraine. The purpose of the test is to evaluate the feasibility of carbonitriding of thermo-strengthened matrix rings and needle-mandrels to improve their stability, hardness, heat resistance, and endurance. If the stability of matrix rings after conventional heat setting varies around 4–6 presses, the rings additionally subjected to chemical-thermal treatment (carbonitration) demonstrated the stability of 7–9 presses due to higher hardness, heat resistance, the formation of a special structure on the surface due to carbonitration in salt melts cyanates and carbonates. Nitrogen and carbon present in the carbonitrided layer slowed down the processes of transformation of solid solutions and coagulation of carbonitride phases. The high hardness of the carbonitrified layer is maintained up to temperatures above 650 °C. If the stability of the needle-mandrels after conventional heat treatment varies between 50–80 presses, the needles, additionally subjected to chemical-thermal treatment (carbonitration) showed the stability of 100–130 presses due to higher hardness, wear resistance, heat resistance, the formation of a special surface structure due to carbonitration in melts of salts of cyanates and carbonates. Keywords: needle-mandrel, matrix ring, pressing, heat treatment, carbonitration.

The mechanisms of scale and subsurface diffusion zone formation of heat-resistant HP40NbTi alloy at long-term high-temperature exposure

Materialia ◽  
2019 ◽  
Vol 7 ◽  
pp. 100427
Author(s):  
Sergey Yu. Kondrat'ev ◽  
Grigoriy P. Anastasiadi ◽  
Alina V. Ptashnik ◽  
Sergey N. Petrov
Keyword(s):  
High Temperature ◽  
Diffusion Zone ◽  
Zone Formation ◽  
High Temperature Exposure ◽  
Heat Resistant ◽  
Temperature Exposure

scholarly journals The possibility of extending work time of tribocouple welding improved stainless steel with improved carbon steel

2018 ◽  
Vol 184 ◽  
pp. 01014 ◽  
Author(s):  
Vlatko Marušić ◽  
Predrag Dašić ◽  
Ivan Opačak
Keyword(s):  
Stainless Steel ◽  
Carbon Steel ◽  
Tensile Load ◽  
High Hardness ◽  
Life Time ◽  
High Yield ◽  
Welding Parameters ◽  
Additional Material ◽  
Tensile Tester ◽  
Bucket Elevator

In the conditions of tribo-corrosion wear, extending of life time of parts can be achieved by using stainless steel, which is hardened to sufficiently high hardness. In the tribopair bolt/shell/slice of the bucket elevator transporter conveyor machine, the previously improved martensitic stainless steel for bolts is hardened at ≈ 45 HRC and welded with the improved high yield carbon steel for bolts. As the additional material, an electrode based on Cr-Ni-Mo (18/8/6) is used. The structure and hardness of welded samples are tested. On the tensile tester, resistance of the welded joint is tested with a simulated experiment. Dimensional control of wear of elements of tribopair was performed after six months in service. The analysis of test results showed that with regulated additional material and by applying the recommended welding parameters, the properties of the weld, which provide the necessary reliability of the joint in the conditions of tensile load, can be achieved, with a significant increase in the wear resistance of bolt.

FACTORS DETERMINING GROWTH OF DIFFUSION LAYERS ON LOW CARBON STEEL AND IRON DURING VACUUM CHROMISING

1996 ◽  
Vol 12 (3) ◽  
pp. 229-234 ◽  
Author(s):  
E. Kasprzycka ◽  
J. Tacikowski ◽  
K. Pietrzak
Keyword(s):  
Carbon Steel ◽  
Low Carbon Steel ◽  
Low Carbon ◽  
Diffusion Layers
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