Optimized carbonate micro-particle production by Sporosarcina pasteurii using response surface methodology

On the wear and damage characteristics of rail material under low temperature environment condition

Abstract Composite layers were obtained by electrochemical deposition of cobalt or nickel from a plating bath with cerium oxide as dispersed particles. The changes in microstructure and microhardness of the composite were studied in correlation with the number of oxide particles incorporated. It was found that the presence of cerium oxide (CeO2) particles has an influence on the codeposition process. The CeO2 included particles lead to structural modifications of the metal matrix and have an effect on the mechanical as well as the surface properties of the composite.

Co-deposition of cerium oxide with nickel and cobalt: correlation between microstructure and microhardness

Fatigue crack growth and damage characteristics of high-speed rail at low ambient temperature

Ferrovanadium is essential for the production of many alloy steels. It is made by the aluminothermic reduction of vanadium oxides, together with scrap steel and burnt lime as a flux at very high temperatures. In this work, the theory of aluminothermic reduction is discussed, and then a computational thermodynamics model is described and its input parameters are discussed and justified. The model predicted very satisfactorily the composition of both the ferrovanadium and waste slag from a heat at the Windimurra smelter in Western Australia. Moreover, the modelling revealed that published data on the activity coefficient of VO1.5 in slag were likely to be seriously in error. It was shown that increasing the recovery of vanadium to the ferroalloy was accompanied by a rapid increase in its aluminium content, which is limited by commercial specifications. The limit on the silicon content of ferrovanadium can only be met by limiting the input of SiO2 to the furnace. The model provides a useful basis for assessi...

Understanding ferrovanadium smelting through computational thermodynamics modelling

The authors have completed thermodynamic calculations of oxidation-reduction processes under submerged arc welding with application of carbon containing additive. The calculations have shown that carbon, due to its high reducing properties under T = 1950 - 2200 K, introduced into the system can significantly decrease the amount of non-metallic inclusions in the weld metal and so improve its mechanical properties.

https://iopscience.iop.org/article/10.1088/1757-899X/91/1/012016/pdf

Some Aspects of Oxidation-Reduction Reactions under Carbon-Bearing Flux Welding

Studied the effect of the introduction of vanadium and cobalt into the charge powder fused wire system Fe-C-Si-Mn-Cr-Ni-Mo-V, used in cladding assemblies and equipment parts and mechanisms operating under abrasive and abrasive shock loads. the cored wires samples were manufactured in the laboratory conditions and using appropriate powder materials and as a carbonfluoride contained material were used the dust from gas purification of aluminum production.

Quality of Metal Deposited Flux Cored Wire with the System Fe-C-Si-Mn-Cr-Mo-Ni-V-Co

Existing methods of rail welding, which are enable to get continuous welded rail track, are observed in this article. Analysis of existing welding methods allows considering an issue of continuous rail track in detail. Metallurgical and welding technologies of rail welding and also process technologies reducing aftereffects of temperature exposure are important factors determining the quality and reliability of the continuous rail track. Analysis of the existing methods of rail welding enable to find the research line for solving this problem.

https://iopscience.iop.org/article/10.1088/1757-899X/253/1/012002/pdf

Modern Methods of Rail Welding

The effect of chemical composition on the microstructure, hardness and wear resistance of the deposited layer of steels 40GMFR and 40H3G2MF was studied. The influence of the content of alloying elements in the examined steels on the structure of the deposited layer was defined, as well the influence of the structure of this layer on the hardness and abrasive wear. A comparative analysis of two steels was performed. Steel 40H3G2MF showed a greater efficacy for surfacing. It had higher hardness, a lower wear rate and a more fine-grained structure.

https://iopscience.iop.org/article/10.1088/1757-899X/150/1/012033/pdf

A study on the properties of the deposited metal by flux cored wires 40GMFR and 40H3G2MF

The influence of a carbon-fluorine additive in AN-348, AN-60, and AN-67 oxidative flux on the welding of 09Γ2C steel and in OK Flux 10.71 basic aluminate flux on the welding of 10XCHД steel is studied experimentally. The composition of the additive is as follows: 14.01–22.72% Al, 13–22.04% F, 13.16–21.34% C, 8.27–13.4% Na, 0.09–0.14% K, 0.66–1.09% Ca, 26.11–42.35% SiO2, 1.15–1.86% FeO, 0.07–0.12% MnO, 0.001–0.1% MgO, 1.47–2.38% S, and 0.03–0.05% P. The experiments show that the use of carbon as the reducing agent is optimal in terms of preventing the formation of nonmetallic inclusions in the weld seam, since its gaseous compounds CO and CO2 are easily captured and do not introduce nonmetallic inclusions in the weld seam. With 4–6% carbon-fluorine additive in the fluxes, the total oxygen content in the seam falls. When using the proposed additive, the mechanical properties and the impact strength at negative temperatures are improved on account of the lower content of nonmetallic inclusions (oxides) in the weld seam. The carbon concentration in the weld seam remains the same as in the basic steel.

https://www.mmse.xyz/wp-content/uploads/Pdf_papers/ID201565RU4.pdf

N. A. Kozyrev

Papers

Some Aspects of Oxidation-Reduction Reactions under Carbon-Bearing Flux Welding

Quality of Metal Deposited Flux Cored Wire with the System Fe-C-Si-Mn-Cr-Mo-Ni-V-Co

Modern Methods of Rail Welding

A study on the properties of the deposited metal by flux cored wires 40GMFR and 40H3G2MF

New carbon-fluorine additives for welding fluxes