A new slurry infiltration method to enhance the wear resistance of bulk graphite with development of reinforced graphitic composites including SiC or Si3N4 hard particles

AbstractNi-based alloy coatings prepared by laser cladding has high bonding strength, excellent wear resistance and corrosion resistance. The mechanical properties of coatings can be further improved by changing the composition of alloy powders. This paper reviewed the improved microstructure and mechanical properties of Ni-based composite coatings by hard particles, single element and rare earth elements. The problems that need to be solved for the particle-reinforced nickel-based alloy coatings are pointed out. The prospects of the research are also discussed.

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Effect on Microstructure and Hardness of Plunger Piston of Fe-Based Composite Coating by Laser Cladding

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.189-193.830 ◽

2011 ◽

Vol 189-193 ◽

pp. 830-833

Author(s):

Yong Tao Zhao ◽

Wen Xue Li ◽

Jun Wei Zhou

Keyword(s):

Wear Resistance ◽

Laser Cladding ◽

Second Phase ◽

Micro Hardness ◽

Hardness Testing ◽

Matrix Metal ◽

Cladding Layer ◽

Hard Particles ◽

The Matrix ◽

Metal Microstructure

The laser cladding of Fe power technology was used to repair worn plunger piston surface. The microstructure of cladding layer, binder course and the matrix were observed by OM and SEM. Besides, the micro-hardness of different zones was measured through micro-hardness testing. The results show that the matrix metal microstructure of plunger piston is made of ferrite and austenite. By laser cladding Fe-based power on base metal, the cladding layer grain is fine and uniform, grain growth has obvious direction and finally become dendrites oriented, the microstructure of cladding layer is both second-phase hard particles and Fe-based solutes. The combination between matrix and cladding layer is smooth, belong to metallurgy bonding. The hardness of cladding layer is higher than that of other parts in three parts, the max value of micro-hardness is about 1250HV, it can agree with wear resistance need of plunge piston surface.

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Electroless deposition bicomponent dispersed phase composite coatings

10.36652/1813-1336-2021-17-02-86-89 ◽

2021 ◽

pp. 86-89

Author(s):

G.M. Mukhametova ◽

A.A. Abrashov ◽

E.G. Vinokurov ◽

V.D. Skopintsev

Keyword(s):

Heat Treatment ◽

Wear Resistance ◽

Succinic Acid ◽

Electroless Deposition ◽

Composite Coatings ◽

Dispersed Phase ◽

Bath Composition ◽

Hard Particles ◽

Coating Composition ◽

Soft Particles

The deposition of bicomponent composite coatings containing both hard and soft particles is studied. Technologically important characteristics (deposition rate, coating composition) of electroless deposition of bicomponent Ni—Cu—P— Cr2O3—MoS2 composite coatings from slightly acidic baths are determined. Bath composition, mol/L: NiSO4 — 0,12; CuSO4 — 0,0016; NaH2PO2 — 0,37; NH2CH2COOH — 0,13; Succinic acid — 0,18; Pb (CH3COO)2 — 10–5; рН 6,5. A mixture of dispersed hard particles (Cr2O3) and soft particles (MoS2) was added to the solution for electroless deposition of a copper doped Ni—P alloy. It was found that when adding a mixture of dispersed Cr2O3 (40...25 % wt.) and MoS2 (60...75 % wt.) at a concentration of 10 g/L, the solution remains stable during deposition and allows the formation of Ni — Cu (1...1.5 wt.%) — P (4 wt.%) — Cr2O3(3 % wt.) — MoS2 (0.12— 0.16 % wt.) coatings at a rate of 15 mg/(cm2 •h). Deposited coatings after heat treatment at 400 °C has a microhardness of 11.1...11.2 GPA. It is concluded that the technology of electroless deposition of bicomponent composite coatings Ni—Cu—P—Cr2O3—MoS2 is promising for obtaining materials with increased hardness and wear resistance.

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Wear Resistance of Laser Clad Hard Particles Reinforced Intermetallic Composite Coating on TA15 Alloy

Chinese Journal of Lasers ◽

10.3788/cjl201239.0203002 ◽

2012 ◽

Vol 39 (2) ◽

pp. 0203002

Author(s):

冯淑容 Feng Shurong ◽

张述泉 Zhang Shuquan ◽

王华明 Wang Huaming

Keyword(s):

Wear Resistance ◽

Composite Coating ◽

Hard Particles ◽

Intermetallic Composite ◽

Ta15 Alloy

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Liquid-phase sintering of BN doped Fe-Cu/TiC composites

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100165793 ◽

1996 ◽

Vol 54 ◽

pp. 666-667

Author(s):

Nuri Durlu ◽

Nan Yao ◽

David L. Milius ◽

Ilhan A. Aksay

Keyword(s):

Wear Resistance ◽

Liquid Phase ◽

Hot Pressing ◽

Liquid Phase Sintering ◽

Electron Microscopic ◽

Hard Particles ◽

Cu Alloys ◽

The Matrix ◽

Full Densification

Fe-Cu composites are commonly produced by liquid phase sintering (above the melting temperature of Cu, 1085°C). The wear resistance of these Fe-Cu alloys can be enhanced by introducing hard particles, e.g., TiC, into the matrix. In such cases, however, the densification of Fe-Cu/TiC composites by liquid phase sintering becomes difficult mainly due to the high wetting angle (110° at 1100-1200°C in argon) of liquid Cu with TiC particles. Especially when the amount of the TiC phase is high enough to form a continuous network of TiC grains, full densification is only achieved through hot pressing. We have recently overcome this problem in an [(Fe-4 wt% Cu) + 30 wt% TiC] composite by the addition of small amounts of BN. Composites with BN additives have been successfully sintered at 1275°C under vacuum or argon by additions of 1 wt% BN. Electron microscopic characterization of these composites has shown that this success is due to the modification of the liquid phase by the addition of BN, which also promotes the liquid phase sintering of the TiC phase.

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Characterization of Al2O3 and SiC Particles, Reinforced Al Powders, and Plasma Sprayed Wear Resistance Coatings

Thermal Spray 2000: Proceedings from the International Thermal Spray Conference ◽

10.31399/asm.cp.itsc2000p0299 ◽

2000 ◽

Author(s):

Fr.-W. Bach ◽

T. Duda ◽

Z. Babiak ◽

P. Bohling ◽

B. Formanek

Keyword(s):

Wear Resistance ◽

Atmospheric Plasma ◽

Mechanically Alloyed ◽

Aluminum Coatings ◽

Hard Particles ◽

Sic Particles ◽

Plasma Sprayed ◽

Aluminum Substrates ◽

Wear Resistance Coatings

Abstract Aluminum coatings reinforced with either Al2O3 or SiC particles were deposited onto aluminum substrates and subjected to various tests. The coatings were made with mechanically alloyed powders via atmospheric plasma spraying (APS). Both types of coatings had uniformly distributed hard particles, porosities in the range of 4 to 5%, and bond strengths of around 20 MPa. The wear resistance of the SiC-reinforced coatings, however, was almost 35% higher than the coatings containing Al2O3. X-ray examination (XRD) showed that the Al2O3 particles undergo partial phase transformation during spraying, making them more prone to wear.

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Adaptation of TiC Hard Particles Properties and Morphology in Metal Matrix Composites by Refractory Elements

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.742.99 ◽

2017 ◽

Vol 742 ◽

pp. 99-105

Author(s):

Andreas Mohr ◽

Arne Röttger ◽

Werner Theisen

Keyword(s):

Wear Resistance ◽

Titanium Carbide ◽

Metal Matrix ◽

Niobium Carbide ◽

Refractory Element ◽

Matrix Composites ◽

Hard Particle ◽

Hard Particles ◽

Size And Morphology ◽

Material Concept

High mechanical loads, corrosion, and abrasion decrease the lifetime of tools. One way to increase the wear resistance of tool materials can be achieved by adding hard particles to the metal matrix such as titanium carbide, which protect the softer metal matrix against abrasive particles. This material concept is designated as metal matrix composite (MMC). Ferro-Titanit® is such MMC material, possessing high wear and a simultaneously high corrosion resistance, for which reason this material is used in the polymers industry. The material concept is based on a corrosion-resistant Fe-base matrix with up to 45 vol% titanium carbide (TiC) as a hard particle addition to improve the wear resistance against abrasion. These TiC hard particles must be adapted to the present tribological system in terms of hardness, size and morphology. This study shows how the size and morphology of TiC hard particles can be influenced by the refractory element niobium (Nb). Therefore, the element Nb was added with 2 and 4 mass% to the soft-martensitic Ferro-Titanit® Grade Nikro128. The investigated materials were compacted by sintering, and the densified microstructure was further characterized by scanning electron microscopy (SEM), energy dispersive spectrometry (EDX), and optical image analyses. Furthermore, microstructure and properties of the compacted Nb-alloyed samples were compared to the reference material Nikro128. The results show that the addition of Nb influences the morphology, size and chemical composition of the TiC hard particle. These changes in the hard phase characteristics also influence the materials properties. It was shown that the phase niobium carbide (NbC) is formed around the TiC during the densification process, leading to a change in morphology and size of the TiC.

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Sol–gel coated B4C particles reinforced 2024 Al matrix composites

Proceedings of the Institution of Mechanical Engineers Part L Journal of Materials Design and Applications ◽

10.1177/1464420711428996 ◽

2011 ◽

Vol 226 (2) ◽

pp. 159-169 ◽

Cited By ~ 4

Author(s):

A Mazahery ◽

M O Shabani

Keyword(s):

Mechanical Properties ◽

Wear Resistance ◽

Base Alloy ◽

Sol Gel ◽

Weight Fraction ◽

Al Alloy ◽

Wear Properties ◽

Weight Losses ◽

Hard Particles ◽

B4c Particles

In this study, mechanical and wear properties of unreinforced 2024 Al alloy and composites with different vol.% of coated and uncoated boron carbide particles were experimentally investigated. It is seen that incorporation of hard particles to 2024 aluminium alloy contributes to the improvement of the mechanical properties and wear resistance of the base alloy to a great extent. Hard particles take part in resisting penetration, cutting, and grinding by the abrasive and protect the surface. It is noted that the increase in the weight fraction of B4C particles improves the wear resistance of the composites. Based on the weight loss data, composites with 30 vol.% B4C particles have the highest wear resistance among all the tested samples and unreinforced aluminium alloys give the lowest wear resistance. The results show that TiB2 coating of the B4C particles improved the mechanical properties. It is observed that the weight losses of the coated composites are less than those of the composites without coating.

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Abrasion Behavior of WC Reinforced Cast Iron Surface Composite Fabricated by Cast-Infiltration Method

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.476-478.555 ◽

2012 ◽

Vol 476-478 ◽

pp. 555-559

Author(s):

Guo Jian Cao ◽

Er Jun Guo ◽

Yi Cheng Feng ◽

Li Ping Wang

Keyword(s):

Wear Resistance ◽

Cast Iron ◽

Sliding Wear ◽

Room Temperature ◽

Matrix Alloy ◽

Volume Fractions ◽

Heat Treated ◽

The Matrix ◽

Infiltration Method ◽

Better Than

In this paper, WC particles and NH4HCO3 powders were mixed evenly, and then pressed under 150MPa. The WC porous preforms were obtained after the compacts being heat treated to eliminate NH4HCO3. The volume ratios of WC in the preforms were 30%, 40% and 50% respectively. WC/Fe composites were fabricated by infiltrating liquid cast iron into the WC porous preforms. Optic microscope and scanning electron microscope were employed to observe the microstructure of the matrix alloy and the composites. The results showed that matrix alloy without WC addition had pores in the surface. The microstructure of the composites with WC volume fractions of 30%, and 40% were denser than that of 50%. Hardness and wet sliding wear behaviors of the composites were investigated at room temperature. The addition of WC particles could effectively improve the hardness and the wear resistance of the composites. The influence of volume fractions on hardness of the composites was similar to that on wear resistance. The hardness and the wear resistance of the 40vol.%WC/Fe composite was better than those of the 30vol.%WC/Fe composite. And the properties of the 50vol.%WC/Fe composite were the worst.

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Application of Self-Propagating High-Temperature Synthesis and Mechanoactivating Treatment for Producing Multi-Component Composite Alloying Materials

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.379.173 ◽

2013 ◽

Vol 379 ◽

pp. 173-177 ◽

Cited By ~ 4

Author(s):

V.I. Yakovlev ◽

A.V. Sobachkin ◽

A.A. Sitnikov

Keyword(s):

Wear Resistance ◽

Surface Layer ◽

High Temperature ◽

Mechanical Activation ◽

Powder Mixture ◽

Core Wire ◽

Temperature Synthesis ◽

New Class ◽

Hard Particles ◽

High Temperature Synthesis

The work is devoted to the important problem of producing new class powdered materials by mechanically activated self-propagating high-temperature synthesis (SHS). Mechanical activation and SHS technologies are discussed; the method of producing powder mixture for the powder electrode core (wire) is discussed. It was established that introducing hard particles (carbides) into the surface layer by means of arc surfacing with SHS-powdered electrodes increases the wear resistance of the welded layer.

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