scholarly journals Influence of Heat Treatment on Structure and Durometric Properties of Coatings Obtained by Surfacing with CSR-04СR27NI7MO3CU2Т Cast Rods

2022 ◽  
Author(s):  
A. Nazarko
Keyword(s):  
Heat Treatment ◽  
Chemical Equipment ◽  
Properties Of Coatings ◽  
Soaking Time ◽  
Wear Resistant ◽  
Chromium Carbides ◽  
Σ Phase ◽  
Austenitic Structure ◽  
Deposited Metal ◽  
Metal Hardness

Abstract. The effect of heat treatment modes on the structure and durometric properties of coatings obtained by surfacing with CSR-04СR27NI7MO3CU2Т cast rods, is considered. It is found that the temperature of 800°С and soaking time of 5 hours are optimal to increase the deposited metal hardness. It is shown that such a phenomenon results from the formation of the austenitic structure hardened by the precipitates of the σ-phase (FeCr), chromium carbides (Cr3C2) and titanium carbides (TiC). The heat treatment modes proposed can be applied in the wear-resistant surfacing technology of chemical equipment parts.

Investigating formation, structure and properties of coatings based on Cu–Ti alloys

2019 ◽  
pp. 175-181
Author(s):  
A. I. Kovtunov ◽  
T. V. Semistenova ◽  
A. M. Ostryanko
Keyword(s):  
Wear Resistance ◽  
Heat Resistance ◽  
Chemical Compound ◽  
Wear Resistant Coating ◽  
Titanium Coating ◽  
Structure And Properties ◽  
Properties Of Coatings ◽  
Wear Resistant ◽  
Ti Alloys ◽  
Titanium Wire

The paper offers technology of argon-arc surfacing with titanium wire in order to form heat and wear resistant coating based on the titanium cuprides. The influence of surfacing modes on the chemical compound and structure of formed coatings is determined. The wear resistance and heat resistance at 600°C and 800°C were researched for copper–titanium coating with 8–63% titanium.

Network Carbide Inheritance during Heat Treatment Process of Large Shield Machine Bearing Steel GCr15SiMn

2015 ◽  
Vol 817 ◽  
pp. 115-120 ◽  
Author(s):  
Dan Zhang ◽  
Le Yu Zhou ◽  
Chao Lei Zhang ◽  
Chao Huang ◽  
Min Zhao ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Treatment Process ◽  
Bearing Steel ◽  
Treatment Temperature ◽  
Heat Treatment Process ◽  
Soaking Time ◽  
Hot Rolled ◽  
Chinese Standard ◽  
Shield Machine ◽  
Quenching And Tempering

Network carbide inheritance during heat treatment process of large shield machine bearing steel GCr15SiMn was investigated by heat treatment experiments and quantitative metallographic. Samples with the proeutectoid cementite network thickness in the range of 0.19~0.54 μm were obtained by changing austenitizing temperature and soaking time of pearlite transformation. The results show that the network in hot rolled bar can be improved when the pre-heat treatment temperature is 950 °C. When the network thickness is above 0.40 μm, the undissolved cementite networks present in microstructures after quenching and tempering. In a Chinese standard, the network grades are 1.5 and 3.0 degree when the networks thickness are 0.40 μm and 0.54 μm, respectively. The critical network thickness that can be eliminated by heat treatment is 0.29 μm.

Influence of Heat Treatment on Residual Stress Formation in the Wear-Resistant Steel 60–Steel 15–Steel 60 Bimetal Material

2021 ◽  
Vol 12 (1) ◽  
pp. 5-9
Author(s):  
N. N. Sergeev ◽  
A. N. Sergeev ◽  
S. N. Kutepov ◽  
A. E. Gvozdev ◽  
A. G. Kolmakov ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Residual Stress ◽  
Resistant Steel ◽  
Wear Resistant ◽  
Stress Formation

scholarly journals Influence of the energy electron beam exposure regimes on the structure and mechanical properties of composite coatings

2020 ◽  
pp. 23-27
Author(s):  
T.A. Krylova ◽  
◽  
Y.A. Chumakov ◽  
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Wear Resistance ◽  
Electron Beam ◽  
Structural Changes ◽  
Composite Coatings ◽  
Initial State ◽  
Austenitic Structure ◽  
Solid Carbide ◽  
Soft Ferrite

The effect of heat treatment on the structure and properties of composite coatings based on chromium carbide with titanium carbide fabricated by non-vacuum electron beam cladding without has been studied. It was shown that tempering leads to a decrease in microhardness and wear resistance, which is associated with the decomposition of the austenitic structure with the formation of a soft ferrite-carbide structure. The post heat treatment tempering was showed to decrease of microhardness and wear resistance, which leads to the decomposition of the austenitic structure with the formation of a soft ferrite-carbide structure. The bulk quenching of coatings after tempering leads to an increase in microhardness comparable to the values of microhardness in the initial state after electron beam cladding, due to the formation of high hard martensite. The wear resistance of composite coatings after tempering is lower than after cladding due to brittle martensite, which is not able to hold solid carbide particles. The composite coatings obtained at the optimal processing conditions have a combination of improved properties and do not require additional heat treatment, resulting in structural changes, causing a decrease in mechanical properties.

scholarly journals Problems Accompanying Repairs of Chemical Equipment

2020 ◽  
pp. 13-19
Author(s):  
Edmund Tasak ◽  
Aneta Ziewiec
Keyword(s):  
Heat Treatment ◽  
High Temperature ◽  
Welded Joints ◽  
Chemical Equipment ◽  
Treatment Processes ◽  
Welding Technology ◽  
Long Time ◽  
Formation Of Cracks

The paper presents problems experienced during repairs of structures operated at high temperature for a long time. Research-related TOFD method-based ultrasonic tests revealed indications implying the presence of unacceptable imperfections in welded joints. Attempted repairs involving the use of welding methods proved ineffective as the welding and heat treatment processes resulted in the formation of cracks. The tests and analysis of the above-named issue revealed that the reason for repair-related problems lay in relaxation cracks triggered by excessively high stresses in the joints and improper parameters of heat treatment to which the steel of the boiler was subjected. The welding technology developed as a result of the study enabled the performance of the proper repair of related equipment and made it possible to re-start the production.

Fatigue Behavior of High Manganese TWIP Steels and of Low Alloy Q&P Steels for Car-Body Applications

2014 ◽  
Vol 783-786 ◽  
pp. 713-720
Author(s):  
Paolo Matteis ◽  
Giorgio Scavino ◽  
R. Sesana ◽  
F. D’Aiuto ◽  
Donato Firrao
Keyword(s):  
Heat Treatment ◽  
Room Temperature ◽  
Fatigue Behavior ◽  
Austenitic Steels ◽  
Fracture Mechanisms ◽  
High Manganese ◽  
Cold Forming ◽  
Austenitic Structure ◽  
Plasticity Effect ◽  
Twip Steels

The automotive TWIP steels are high-Mn austenitic steels, with a relevant C content, which exhibit a promising combination of strength and toughness, arising from the ductile austenitic structure, which is strengthened by C, and from the TWIP (TWinning Induced Plasticity) effect. The microstructure of the low-alloy Q&P steels consists of martensite and austenite and is obtained by the Quenching and Partitioning (Q&P) heat treatment, which consists of: austenitizing; quenching to the Tqtemperature, comprised between Msand Mf; soaking at the Tppartitioning temperature (Tpbeing equal to or slightly higher than Tq) to allow carbon to diffuse from martensite to austenite; and quenching to room temperature. The fatigue behavior of these steels is examined both in the as-fabricated condition and after pre-straining and welding operations, which are representative of the cold forming and assembling operations performed to fabricate the car-bodies. Moreover, the microscopic fracture mechanisms are assessed by means of fractographic examinations.

scholarly journals Indigenous Scheming and Manufacturing of a Laboratory Scale Heat Treatment Furnace - Technical Report

2017 ◽  
Vol 12 (1) ◽  
pp. 151-161
Author(s):  
M. Wahaj ◽  
M. Asim ◽  
A. W. Owais ◽  
A. W. Waqas ◽  
S. Anwar Ul Hasson
Keyword(s):  
Heat Treatment ◽  
Developed Countries ◽  
Laboratory Scale ◽  
Soaking Time ◽  
Heat Treatment Furnace ◽  
Research Activities ◽  
Treatment Furnace ◽  
Technical Report ◽  
Commercial Market ◽  
Electric Heat

In order to contribute in the research activities related to heat treatment of metals and other engineering materials, a laboratory scale heat treatment furnace is essentially required. Among several other types of furnaces, electric heat treatment furnace is said to be most useful. It is provided with a programmable controller which precisely controls heating rate, soaking time and cooling rate. The controller also helps in keeping the heat treatment safe by emergency turnoff facility. This manuscript reports the indigenous designing and development of electrical heat treatment furnace, which not only provides enormous learning to fresh graduates but also saved a handsome amount, which could have spent in purchasing same article from commercial market. In this paper, the sequential procedure of furnace designing and development is being shared with the engineering community so that the researchers of under developed countries may save their esteemed educational and research funds.Journal of the Institute of Engineering, 2016, 12(1): 151-161 

Microstructure of Built Part Obtained by Powder Bed Fusion Process with Metal

2019 ◽  
Vol 825 ◽  
pp. 1-6
Author(s):  
Tatsuaki Furumoto ◽  
Kyota Egashira ◽  
Souta Matsuura ◽  
Makoto Nikawa ◽  
Masato Okada ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Metal Powder ◽  
Maraging Steel ◽  
Process Parameters ◽  
Steel Powder ◽  
Powder Bed Fusion ◽  
Laser Melting ◽  
Powder Bed ◽  
Suitable Heat Treatment ◽  
Deposited Metal

The influence of various process parameters on the building of maraging steel powder by the selective laser melting (SLM) processes is investigated. The microstructure in the built part was observed and the influence of the heat treatment was evaluated. As results, the depth of solidified layer was higher than that of deposited metal powder, and its value was influenced with the process parameters. The microstructure in the boundary between the built part and the substrate was quite different from the built part even if the suitable heat treatment was performed.

Microstructure Evolution in Isothermal Heat Treatment of 0Cr32Ni7Mo4NDuplex Stainless Steel

2014 ◽  
Vol 789 ◽  
pp. 314-319
Author(s):  
Yu Lai Chen ◽  
Hong He ◽  
Fei Fang
Keyword(s):  
Heat Treatment ◽  
Stainless Steel ◽  
Microstructure Evolution ◽  
Volume Fraction ◽  
Decomposition Reaction ◽  
Optical Microscope ◽  
Isothermal Heat Treatment ◽  
Σ Phase ◽  
Temperature Range ◽  
Δ Phase

The microstructure evolution of as-cast 0Cr32Ni7Mo4N hyper duplex stainless steel during the isothermal heat treatment in the temperature range of 800°C-1300°Cwas studied in the present investigation. The morphologies and precipitates were observed and determined by using optical microscope (OM), scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS). The results show that eutectoid decomposition reaction (δ→σ+γ2) take place in ferrite (δ) phase during isothermal heat treatment in the temperature range of 800°C-1000°C. Sigma (σ) phase and secondary austenite (γ2) phase coexist as cellular structure. Lamellar Cr2N precipitates in δ phase mostly when isothermal heat treatment at 800°Cand 850°C, while it only appears in γ phase between 900°C and 1050°C. As the annealing temperature rising, the quantity of σ phase, Cr2N and γ2 phase decreases. The volume fraction ratio of ferrite and austenite is stable between 1100°C and 1300°C, and γ → δ transformation is hard to occur.

Degradation of phenol by using magnetic photocatalysts of titania

2013 ◽  
Vol 67 (7) ◽  
pp. 1434-1441 ◽  
Author(s):  
Chiung-Fen Chang ◽  
I.-Peng Tseng
Keyword(s):  
Heat Treatment ◽  
Photocatalytic Activity ◽  
Single Phase ◽  
Health Impacts ◽  
X Ray Diffraction ◽  
Final Temperature ◽  
Soaking Time ◽  
X Ray ◽  
Green Materials ◽  
Diffraction Patterns

Magnetic TiO2 (MT) composites were prepared and applied to degrading phenol, which is one of the listed priority pollutants. The effects of heat treatment under preparation on the photocatalytic activity of MT composites have been investigated by varying the soaking time under a constant final temperature of 823 K. The total organic carbon and ring-remaining intermediates of o-DHB, p-DHB and 1,4-BQ in solution were detected during the photodegradation of phenol. All the resulting MT composites were the single-phase anatase and magnetite judged by X-ray diffraction patterns. The calcination of the as-prepared particles was proven to be extremely crucial to the photocatalytic activity. The best condition of heat treatment was found to be soaking time of 2 h at T = 823 K due to the good performance of photocatalytic activity, stable magnetic property, and reusability over three times. The results lead to the conclusion that recyclable MT composites prepared in this study, which belonged to the category of recyclable green materials, exhibit good photocatalytic activity to degrade phenol so as to possess applicable potential for the degradation of refractory organics in the aqueous solution. Furthermore, the environmental and health impacts were reduced as MT composites were applied in the treatment of water pollution.

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