INVESTIGATION ON TRIBOLOGICAL BEHAVIOR OF DUCTILE CAST IRONS WITH NANOSIZED PARTICLES

The work in this study is focused on investigation of the tribological behavior of ductile cast iron with nanosized particles: titanium nitride TiN; titanium nitride 30% + titanium carbonitride 70% (30%TiN+70%TiCN). The ductile cast iron composition is: Fe-3,55C-2,67Si-0,31Mn-0,009S-0,027P-0,040Cu-0,025Cr-0,08Ni-0,06Mg wt%. Before the addition to the melt nanosized particles were coated with nickel by the electroless nickel deposition method EFFTOMNICKEL .The nickel coating on the nanosized particles ensures their wetting in the melt as well as their uniform distribution into the cast. The optical and quantity metallographic observations and wear test are performed to study the influence of the nanoparticle additives on the cast iron tribological properties. It is observed that the quantity proportion changes between pearlite, ferrite and graphite phase in the cast iron structure. The graphite shape is retained the same, but the nanosized additives decrease the average diameter of the graphite spheres Dmid and increase the quantity of the graphite phase in the structure of ductile cast irons. The cast iron wear resistance in the presence of nanosized additives of (TiN+TiCN) and TiN increases to 55–69% in comparison to wear resistance of the cast iron without nanoparticles.

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Study on the Plasma Beam Surface Remelting Modification of Nodular Cast Iron

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.152-153.1751 ◽

2010 ◽

Vol 152-153 ◽

pp. 1751-1754 ◽

Cited By ~ 1

Author(s):

Li Yang ◽

Gang Li

Keyword(s):

Wear Resistance ◽

Cast Iron ◽

Nodular Cast Iron ◽

Hardened Layer ◽

Ductile Cast Iron ◽

Graphite Phase ◽

Plasma Beam ◽

Hardness Tester ◽

Operating Current ◽

And Performance

To improve the wear resistance of ductile cast iron, plasma beam remelt-solidified hardening on the surface is adopted. Scanning electron microscope and micro-hardness tester is used to analyze the microstructure and performance for plasma beam remelt-solidified layer of nodular cast iron. The results show that micromelted-solidified hardening of the nodular cast iron surface can be obtained when the operating current is up to 50A. Along with the operating current increases, the width and depth of remelt-solidified layer and hardened layer increase, but the hardness goes down. After the hardening, graphite phase in remelt-solidified region is vanishing. The microstructure of remelt-solidified region is tiny ledeburite and remained austenite and of transformation hardening region is acicular martensite, remained austenite，spheroid graphite and ferrite .In transition region, martensite shell around nodular graphite appears, which is advantageous to enhance the wear resistance. From the surface to inner, the microhardness declines first and then increases, after achieving the maximum value the hardness slowly drops. The highest microhardness appears at the second-surface layer which has a certain distance to the surface.

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Bainitic Cast Irons with Nanosized Particles

Materials Science Forum ◽

10.4028/www.scientific.net/msf.994.104 ◽

2020 ◽

Vol 994 ◽

pp. 104-111

Author(s):

Julieta Atanasova Kaleicheva ◽

Valentin Plamenov Mishev ◽

Zdravka Kirilova Karaguiozova

Keyword(s):

Titanium Nitride ◽

Abrasive Wear ◽

Mechanical Characteristics ◽

Titanium Carbonitride ◽

Wear Testing ◽

Nanosized Particles ◽

Cast Irons ◽

X Ray ◽

Bainitic Structure ◽

Kinetics Of

In the present study austempered ductile irons (ADI) with lower bainitic structure are investigated. Nanosized particles (50nm) of titanium carbonitride + titanium nitride TiCN+TiN and titanium nitride TiN are added to the casting volume. The samples microstructure is studied by optical metallography and X-Ray analysis. The influence of the nanosized additives on the kinetics of the bainitic transformation and on the morphology of the bainitic structure is investigated. The abrasive wear testing, hardness measurements and impact strength are carried out. It is established that the presence of nanoadditives in the bainitic cast irons leads to the changes in their microstructure which increases their mechanical characteristics and abrasive wear resistance. The studied nanocomposite materials expand the potential for new ADI applications in the industry.

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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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Application of the optimally alloyed cast irons in order to increase the durability and to ensure the cost reduction of mining and metallurgical products

E3S Web of Conferences ◽

10.1051/e3sconf/202130301005 ◽

2021 ◽

Vol 303 ◽

pp. 01005

Author(s):

Dmitry Lubyanoi ◽

Evgeny Pudov ◽

Evgeny Kuzin ◽

Olga Semenova

Keyword(s):

Wear Resistance ◽

Cast Iron ◽

Operational Reliability ◽

Cast Irons ◽

Metallurgical Production ◽

Alloyed Cast ◽

Alloyed Cast Iron ◽

And Performance ◽

Working Bodies ◽

The Cost

The article shows the relevance of the use of alloyed cast iron in mining and metallurgical engineering. The article discusses the technologies for producing naturally alloyed cast iron. For working bodies and friction units of mining machines, such as pumps, coal pumps, hydrocyclones, crushers and mills. The main type of wear for them is abrasive. To increase the wear resistance of cast iron the production of cast iron has not been sufficiently studied yet. Although the use of cast iron in a complex alloyed with manganese, silicon, chromium, titanium and vanadium has been studied. The article studies the influence of manganese, titanium and vanadium on the mechanical properties and performance of machine parts and products of mining and metallurgical production in contact with high-temperature and highly abrasive media. The rational content of titanium and vanadium in gray cast irons is established in the range of 0.05-0.1%, which ensures their heat resistance and increases their wear resistance. The content of these elements can be increased to 0.07-0.12%. Bushings made of this cast iron have the required wear resistance and can increase the operational reliability of the equipment in the conditions of mining and metallurgical production. They also replace non-ferrous metals, as well as products obtained by powder metallurgy methods.

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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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Modifying of the Surface of Products from Cast Iron as the Element of Production Modernization

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.299.588 ◽

2020 ◽

Vol 299 ◽

pp. 588-593

Author(s):

Nataliia Vodolazskaya ◽

Olga Sharaya

Keyword(s):

Wear Resistance ◽

Cast Iron ◽

Saturation Temperature ◽

Thermochemical Treatment ◽

Structural Condition ◽

Surface Wear ◽

Layer Depth ◽

Cast Irons ◽

Process Duration ◽

Surface Impregnation

The way of solving the problem of surface wear of products from cast iron due to development of technological processes of its strengthening treatment is offered in this article. Receiving the hardened skins is reached by purposeful formation of the set structural condition of metal by methods of surface impregnation, i.e., modifying. Results of researches on thermochemical treatment of cast irons of grades EN-GJL-250, EN-JS1060 are presented The micro-structural analysis showed that with rising the saturation temperature and increasing the process duration the layer depth cartbonitration increases. Studying the samples for wear resistance carried out on stand ММ 295 showed that for grade EN-GJL-250 it increased 2,2 times, and for grade EN-JS1060 – 3 times as compared to the initial (non-modified) state. Experimental-industrial tests of products of cast iron (model accessory, parts of homogenizing pumps) after carbonitration permitted to state 2-4 times of its surface.

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Effect of specimen preparation on contact fatigue wear resistance of austempered ductile cast iron

Wear ◽

10.1016/j.wear.2007.01.078 ◽

2007 ◽

Vol 263 (1-6) ◽

pp. 663-668 ◽

Cited By ~ 18

Author(s):

C. Brunetti ◽

M.V. Leite ◽

G. Pintaude

Keyword(s):

Wear Resistance ◽

Cast Iron ◽

Contact Fatigue ◽

Ductile Cast Iron ◽

Specimen Preparation ◽

Fatigue Wear ◽

Austempered Ductile Cast Iron

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Influence of Ca-Ba and Sr Base Inoculants on Metallurgical and Mechanical Properties of Grey and Ductile Cast Irons

Volume 12: Materials: Genetics to Structures ◽

10.1115/imece2018-86448 ◽

2018 ◽

Author(s):

Dhruv Patel ◽

Devendra Parmar ◽

Siddharthsinh Jadeja

Keyword(s):

Mechanical Properties ◽

Cast Iron ◽

Uniform Distribution ◽

Ductile Cast Iron ◽

Grain Structure ◽

Spheroidal Graphite ◽

Primary Carbide ◽

Cast Irons ◽

Melt Temperature ◽

Nodular Graphite

Microstructural adaptation of cast iron alloys by inoculation is a well-known practice to swell their mechanical properties. In foundries, several inoculants have been used to refine grain structure, and to obtain uniform distribution of graphite flakes. Inoculation is one of the most critical steps in cast iron production. The effectiveness of inoculants depends on melt temperature, method of addition, type of inoculants, and holding time. In this paper, the effect of Ca-based, Ba-based, Ca-Ba based and Sr-based inoculants on microstructure and tensile properties of grey cast iron IS-210 and spheroidal graphite iron IS-1862 is reported. Results showed both Ca and Ba based inoculants were effective in obtaining uniform distribution of flaky and nodular graphite in IS-210, and IS-1862 cast irons, respectively. But in a case of Sr-based inoculant were highly effective for increase the nodularity of SG cast iron as well as succeed supreme yield strength for both grey and ductile cast iron. The amounts of ferrite in the as-cast matrix are excess with controlled granulometry for elimination of primary carbide in Sr-based inoculant.

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