CJ90-01. On the microstructure and wear resistance of composite of carbide particle with white cast iron as base-alloy

Abstract In order to increase wear resistance cast steel casting the TiC-Fe-Cr type composite zones were fabricated. These zones were obtained by means of in situ synthesis of substrates of the reaction TiC with a moderator of a chemical composition of white cast iron with nickel of the Ni-Hard type 4. The synthesis was carried out directly in the mould cavity. The moderator was applied to control the reactive infiltration occurring during the TiC synthesis. The microstructure of composite zones was investigated by electron scanning microscopy, using the backscattered electron mode. The structure of composite zones was verified by the X-ray diffraction method. The hardness of composite zones, cast steel base alloy and the reference samples such as white chromium cast iron with 14 % Cr and 20 % Cr, manganese cast steel 18 % Mn was measured by Vickers test. The wear resistance of the composite zone and the reference samples examined by ball-on-disc wear test. Dimensionally stable composite zones were obtained containing submicron sizes TiC particles uniformly distributed in the matrix. The macro and microstructure of the composite zone ensured three times hardness increase in comparison to the cast steel base alloy and one and a half times increase in comparison to the white chromium cast iron 20 % Cr. Finally ball-on-disc wear rate of the composite zone was five times lower than chromium white cast iron containing 20 % Cr.

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Alloyed White Cast Iron with Precipitates of Spheroidal Vanadium Carbides VC

Archives of Foundry Engineering ◽

10.2478/v10266-012-0113-y ◽

2012 ◽

Vol 12 (4) ◽

pp. 95-100 ◽

Cited By ~ 5

Author(s):

M. Kawalec ◽

M. Górny

Keyword(s):

Mechanical Properties ◽

Wear Resistance ◽

Cast Iron ◽

Master Alloy ◽

Eutectic Composition ◽

White Cast Iron ◽

Base Alloy ◽

Cast Steel ◽

Abrasive Wear Resistance ◽

Vanadium Carbides

Abstract The paper presents the results of tests on the spheroidising treatment of vanadium carbides VC done with magnesium master alloy and mischmetal. It has been proved that the introduction of magnesium master alloy to an Fe-C-V system of eutectic composition made 34% of carbides crystallise in the form of spheroids. Adding mischmetal to the base alloy melt caused 28% of the vanadium carbides crystallise as dendrites. In base alloy without the microstructure-modifying additives, vanadium carbides crystallised in the form of a branched fibrous eutectic skeleton. Testing of mechanical properties has proved that the spheroidising treatment of VC carbides in high-vanadium cast iron increases the tensile strength by about 60% and elongation 14 - 21 times, depending on the type of the spheroidising agent used. Tribological studies have shown that high-vanadium cast iron with eutectic, dendritic and spheroidal carbides has the abrasive wear resistance more than twice as high as the abrasion-resistant cast steel.

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The Joint Effects of Nitriding and Parameters Related to the Destabilisation of Austenite on Wear Resistance in White Cast Iron with 25% Cr

Metals ◽

10.3390/met11010085 ◽

2021 ◽

Vol 11 (1) ◽

pp. 85

Author(s):

Alejandro González-Pociño ◽

Florentino Alvarez-Antolin ◽

Juan Asensio-Lozano

Keyword(s):

Wear Resistance ◽

Cast Iron ◽

White Cast Iron ◽

Nitrided Layer ◽

Erosive Wear ◽

Air Cooling ◽

Cast Irons ◽

Eutectic Carbides ◽

Noticeable Increase ◽

Ionic Nitriding

In this article, the effects of an ionic nitriding treatment are analysed, together with deliberate variation of different thermal parameters associated with the destabilisation of austenite, on erosive wear resistance of white cast irons with 25% Cr. The methodology followed in this research was an experimental design, where six factors were analyzed by performing eight experiments. The thickness of the nitrided layer is much smaller than in white cast iron with lower percentages in Cr, never reaching 20 microns. The nitriding treatment entails considerable softening of the material underneath the nitriding layer. This softening behaviour becomes partially inhibited when the destabilisation temperature of austenite is 1100 °C and dwell times at such temperature are prolonged. This temperature seems to play a significant role in the solubilization of non-equilibrium eutectic carbides, formed during industrial solidification. The nitriding treatment leads to additional hardening, which, in these cases, favours a second destabilisation of austenite, with additional precipitation of secondary carbides and the transformation of retained austenite into martensite. Despite softening of the material, the nitriding treatment, together with air-cooling after destabilisation of the austenite, allows a noticeable increase in resistance to erosive wear.

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Study of the durability of the working body the dryer

Sel'skohozjajstvennaja tehnika: obsluzhivanie i remont (Agricultural Machinery: Service and Repair) ◽

10.33920/sel-10-2005-09 ◽

2020 ◽

pp. 56-60

Author(s):

A. P. Chernysh

Keyword(s):

Heat Treatment ◽

Wear Resistance ◽

Cast Iron ◽

White Cast Iron ◽

Low Cost ◽

Functional Surface ◽

Wear Coatings

In this article, the plant for heat treatment of grain material, namely perfo-rated spiral operating part, developed by the authors was chosen as the object of improving the wear resistance. The research was conducted in the laboratory of the Technology of Metals and Machinery Repair Department of Kemerovo State Agricultural Institute. The aim of the research is to select the most appropriate method of hardening the functional surface of perforated spiral operating part with the use of low-cost anti-wear coatings. The basis for choosing the method of surfacing the coating was the use of a method of forming the technological repair units (TRU), which allowed electric spark treatment with unalloyed white cast iron.

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Analysis of the Structure and Abrasive Wear Resistance of White Cast Iron with Precipitates of Carbides

Archives of Metallurgy and Materials ◽

10.2478/amm-2013-0113 ◽

2013 ◽

Vol 58 (3) ◽

pp. 973-976 ◽

Cited By ~ 9

Author(s):

D. Kopyciński ◽

M. Kawalec ◽

A. Szczęsny ◽

R. Gilewski ◽

S. Piasny

Keyword(s):

Wear Resistance ◽

Cast Iron ◽

Abrasive Wear ◽

Metal Matrix ◽

White Cast Iron ◽

Abrasive Wear Resistance ◽

Operating Conditions ◽

Metallographic Analysis ◽

Abrasive Hardness ◽

Resistance Tests

Abstract The resistance of castings to abrasive wear depends on the cast iron abrasive hardness ratio. It has been anticipated that the white cast iron structure will be changed by changing the type of metal matrix and the type of carbides present in this matrix, which will greatly expand the application area of castings under the harsh operating conditions of abrasive wear. Detailed metallographic analysis was carried out to see the structure obtained in selected types of white cast iron, i.e. with additions of chromium and vanadium. The study compares the results of abrasive wear resistance tests performed on the examined types of cast iron.

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Effect of the Morphology, Size, Distribution and Homogeneity of Carbides and Matrix on Wear Resistance in High Cr-Alloys White Cast Iron

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1016.56 ◽

2021 ◽

Vol 1016 ◽

pp. 56-62

Author(s):

Carlos Camurri ◽

Jasmín Maril ◽

Eric Romero

Keyword(s):

Wear Resistance ◽

Cast Iron ◽

White Cast Iron ◽

Wear Behavior ◽

Hardness Test ◽

Mining Equipment ◽

Cast Irons ◽

Loss Of Mass ◽

Ultimate Purpose ◽

Wear Tests

The aim of this work was to study the wear behavior of high-chromium white cast iron of families ASTM A-532 II (B, D) and III A, used in mining equipment, in order to establish relationships between the wear resistance, hardness and microstructure of the alloys, with the ultimate purpose of predicting their resistance to abrasion. Samples from these cast irons were subjected to mechanical wear tests by rotating drum, then their micro/macro hardness was measured and microstructure analyzed by optical and scanning electron microscopy .It was found that when the macroscopic hardness differences were significant there was a strong correlation between the hardness and the loss of mass due to abrasion-impact wear. By contrast, when the alloys had similar hardness, the wear resistance was determined by morphology, size, and the distribution and connectivity of carbides and matrix and therefore was not predictable by an only simple hardness test.

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