Studying of properties and microstructure of 30 CrMnV9 steel on wear resistance

The properties and microstructure of 30 CrMoV9 steel after its treatment with ferronickel and ferromanganese with the aim of increasing the content of nickel and manganese in steel were studied. After the trial smelting, the samples were tested in four parameters: hardness, ultimate stress limit, wear resistance, and toughness. Experimental studies have shown that changing the composition of steel with increasing the nickel content up to 0,5 – 0,7 % and manganese up to 1,5 – 1,8 % leads to increasing strength, hardness and wear resistance of steel with slight decreasing its toughness

Heat treatment effect on the properties of vibration treated steel during crystalization

The effect of heat treatment on the structure and properties of 30HGSNMA steel that has been subjected to vibration treatment at the stage of primary crystallization is considered in the work. It is proposed to use normalization with accelerated cooling with a water-air mixture among possible treatment methods. The properties of steel after this heat treatment are investigated. It has been found that there is a significant increasing of hardness, tensile strength and impact strength, and the level of these properties is comparable with the level of properties after hardening and tempering. The introduction of one-stage heat treatment that consists in normalization with accelerated cooling, allows reducing the heat treatment cycle and increasing the equipment productivity

Chromium-nickel cast iron composition effect on properties and graphitization process

The paper considers the cast iron based on nihard-2 composition effect on the properties and process of graphitization. It is shown that changing the Cr:Si ratio equal to 2:1 leads to the development of the graphitization process, as a result of which lamellar graphite appears in the structure. Subsequent modification leads to changing the shape of the graphite into the nodular one, which leads to some decrease in hardness but increases resistance to abrasive wear by about 20-25 %

Investigation of heat-resistant properties and microstructure of experimental steel based on the Cr-Ni-Ti-Nb system obtained under industrial conditions

The Nb effect on long-term strength of Cr18Ni10Ti steel is considered. There is substantiated selecting this steel for obtaining cast parts for metallurgical furnaces. It is shown that introduction of Nb in the amount of 1 % into steel of a given composition increases tensile strength and long-term strength by 15 %. Improving the properties is associated with the formation of NbC carbides

Chromium-nickel cast iron composition effect on properties and graphitization process

The paper considers the cast iron based on nihard-2 composition effect on the properties and process of graphitization. It is shown that changing the Cr:Si ratio equal to 2:1 leads to the development of the graphitization process, as a result of which lamellar graphite appears in the structure. Subsequent modification leads to changing the shape of the graphite into the nodular one, which leads to some decrease in hardness but increases resistance to abrasive wear by about 20-25 %

Studying the properties and microstructure of parts obtained by different casting technologies

The paper presents some data of studying the microstructure, properties and surface quality of parts obtained in different modes. It is shown that in the case of quenching and tempering (QT) in the process of primary crystallization by vibration, in the future it becomes possible to replace QT with a simpler and cheaper method: normalization with accelerated air-water cooling. After this treatment, the steel structure is characterized by almost the same parameters as after QT. Tensile strength, hardness, average grain size are comparable with the performance of QT steels

Comparative analysis of graphite inclusions in chrome cast iron structure

The paper presents the results of a quantitative metallographic analysis of graphite inclusions in the structure of chrome cast irons including cast iron of the Nihard class, as well as after treatment with titanium carbide. The ThixometPro software was used for the analysis. The shape, size, perimeter, distribution density of graphite inclusions, as well as the area occupied by the structural components and their dispersion were evaluated. It is shown that the introduction of titanium carbide has a favorable effect on the pattern of graphite inclusions and some parameters of the structure in general

Studying refractory bricks structure impact on their performance properties

The refractory bricks structure impact on such operational properties as slag resistance and heat resistance is considered. Chamotte brick used in the RK metallurgical plants and refractory brick made according to the new technology with the use of non-stationary pressure have been used as samples. The products porosity has been studied. It has been shown that porosity, slag resistance and heat resistance of products manufactured using non-stationary pressure is higher than those of the reference