Increase in Hardness and Wear Resistance of Ti-6Al-4V Surface by In Situ Laser Coating of Ti- and Al-Based Hard Ceramics

The possibility of deposition of Fe–TiC nanocomposite on the surface of carbon steel substrate with the laser coating method had been investigated. Mechanical milling was used for the preparation of raw materials. The mixture of milled powders was used as a coating material on the substrate steel surface and a CO2 laser was used in continuous mode for coating. Microstructural studies were performed by scanning electron microscopy. Determinations of produced phases, crystallite size and mean strain have been done by X-ray diffraction. The hardness and wear resistance of coated samples were measured. The results showed that the in situ formation of Fe–TiC nanocomposite coating using laser method is possible. This coating has been successfully used to improve the hardness and wear resistance of the substrate so that the hardness increased by about six times. Coated iron and titanium carbide crystallite sizes were in the nanometer scale.

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Fabrication of SiC Particulates Reinforced MoSi2 Composite Coating by Laser Cladding

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.373-374.304 ◽

2008 ◽

Vol 373-374 ◽

pp. 304-307

Author(s):

Sen Yang ◽

Ming Run Wang ◽

Tao Gong ◽

Wen Jin Liu

Keyword(s):

Wear Resistance ◽

Laser Cladding ◽

Continuous Wave ◽

Steel Substrate ◽

Laser Output Power ◽

Scanning Velocity ◽

Sic Particulates ◽

Metallurgical Bond ◽

Improve Wear Resistance

In order to improve wear resistance of carbon steel, laser cladding experiments were carried out using a 3kW continuous wave CO2 laser. The diameter of the laser beam was 3-5mm, the scanning velocity was 3-10mm/s, and the laser output power was 1.0-1.3kW. The experimental results showed that MoSi2/SiCP composites coating could be in-situ synthesized from mixture powders of molybdenum, silicon and SiC by laser cladding. A good metallurgical bond between the coating and the substrate could be achieved. The microstructures of the coating were mainly composed of MoSi2, SiC and FeSiMo phases. The average microhardness of the coating was about HV0.21300, about 6.0 times larger than that of steel substrate.

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Room-temperature wear resistance of tungsten carbide composite layers produced on gray cast iron by diffusion-controlled in situ reactions

Surface and Coatings Technology ◽

10.1016/j.surfcoat.2021.127649 ◽

2021 ◽

pp. 127649

Author(s):

Xiaolong Cai ◽

Huanxi Wang ◽

Yunhua Xu ◽

Baowei Cao ◽

Mingxin Liu ◽

...

Keyword(s):

Wear Resistance ◽

Cast Iron ◽

Tungsten Carbide ◽

Room Temperature ◽

Gray Cast Iron ◽

Composite Layers ◽

Diffusion Controlled ◽

In Situ Reactions ◽

Tungsten Carbide Composite

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Effects of TiB2/TiCxratios on compression properties and abrasive wear resistance of in situ 50 vol.-% (TiB2–TiCx)/Al–Cu composites

Powder Metallurgy ◽

10.1080/00325899.2017.1400221 ◽

2017 ◽

Vol 61 (1) ◽

pp. 81-87 ◽

Cited By ~ 1

Author(s):

Lei Wang ◽

Feng Qiu ◽

Delong Yang ◽

Jingyuan Liu ◽

Fang Chang ◽

...

Keyword(s):

Wear Resistance ◽

Abrasive Wear ◽

Abrasive Wear Resistance ◽

Compression Properties

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A Low Temperature CVD Process for TiN Coatings

MRS Proceedings ◽

10.1557/proc-168-311 ◽

1989 ◽

Vol 168 ◽

Cited By ~ 1

Author(s):

A. Aguero ◽

D. Little ◽

P. Lowden

Keyword(s):

Wear Resistance ◽

Low Temperature ◽

Titanium Nitride ◽

Vapour Deposition ◽

Chemical Vapour ◽

Reduced Pressure ◽

Tin Coatings ◽

Excellent Adhesion ◽

Low Temperature Process

AbstractA novel low temperature process for the chemical vapour deposition of titanium nitride films has been developed. Titanium sub-halides generated “in situ” by chlorination of titanium pellets are subsequently reacted with ammonia at reduced pressure and temperatures of 450–600° C. The coatings have excellent adhesion and wear resistance. A description of the process and the properties of the coatings produced by it will be presented.

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Accelerated degradation of polyetheretherketone and its composites in the deep sea

Royal Society Open Science ◽

10.1098/rsos.171775 ◽

2018 ◽

Vol 5 (4) ◽

pp. 171775 ◽

Cited By ~ 2

Author(s):

Hao Liu ◽

Jianzhang Wang ◽

Pengfei Jiang ◽

Fengyuan Yan

Keyword(s):

Mechanical Properties ◽

Wear Resistance ◽

Hydrostatic Pressure ◽

Deep Sea ◽

Normal Pressure ◽

Wear Behaviour ◽

Special Equipment ◽

Accelerated Degradation ◽

Seawater Environment

The performance of polymer composites in seawater, under high hydrostatic pressure (typically few tens of MPa), for simulating exposures at great depths in seas and oceans, has been little studied. In this paper, polyetheretherketone (PEEK) and its composites reinforced by carbon fibres and glass fibres were prepared. The seawater environment with different seawater hydrostatic pressure ranging from normal pressure to 40 MPa was simulated with special equipment, in which the seawater absorption and wear behaviour of PEEK and PEEK-based composites were examined in situ . The effects of seawater hydrostatic pressure on the mechanical properties, wear resistance and microstructure of PEEK and its composites were focused on. The results showed that seawater absorption of PEEK and its composites were greatly accelerated by increased hydrostatic pressure in the deep sea. Affected by seawater absorption, both for neat PEEK and composites, the degradation on mechanical properties, wear resistance and crystallinity were induced, the degree of which was increasingly serious with the increase of hydrostatic pressure of seawater environment. There existed a good correlation in an identical form of exponential function between the wear rate and the seawater hydrostatic pressure. Moreover, the corresponding mechanisms of the effects of deep-sea hydrostatic pressure were also discussed.

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Effect of in situ formation of tungsten semicarbide on the microstructure and mechanical properties of medium carbon steel composites

Metallurgical Research & Technology ◽

10.1051/metal/2021080 ◽

2021 ◽

Vol 118 (6) ◽

pp. 606

Author(s):

Nandish Girishbhai Soni ◽

Akash Ganesh Mahajan ◽

Kaustubh Ramesh Kambale ◽

Sandeep Prabhakar Butee

Keyword(s):

Mechanical Properties ◽

Particle Size ◽

Wear Resistance ◽

Carbon Steel ◽

Sintered Density ◽

Medium Carbon Steel ◽

Complete Conversion ◽

Medium Carbon ◽

In Situ Formation

Fabrication with the in-situ formation of W2C reinforced medium carbon steel (MCS) MMC’s was attempted using W or WO3 and graphite addition to steel. The P/M route comprising milling, compaction and sintering at 1050 °C and 1120 °C respectively in 90% N2 + 10% H2 atmosphere was adopted. Both SEM and BET studies revealed the particle size to be around 100, 7 and 40 µm for MCS, W and WO3, respectively. A complete conversion of tungsten into tungsten semicarbide (W2C) was noted in XRD for the tungsten additions of ∼6, 9 and 12 wt.% with stoichiometrically balanced C (graphite) addition of 0, 0.2 and 0.4 wt.%. However, WO3 + C addition (balanced as above) revealed the partial conversion of WO3 to W2C. The peaks of Fe3C were observed only for MCS + W + C samples and not for MCS + WO3 + C samples in XRD. In SEM, the WO3 phase appeared porous and partially converted, whereas, W2C phase was dense. Sintered density improved for the addition of W, whereas it monotonically reduced for WO3 addition to MCS + C samples. Higher hardness, compressive strength, and wear resistance was noted for W addition than WO3 to MCS+C samples.

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Microstructural Characterization, Mechanical Properties and Wear Resistance of TiCP Reinforced Ni-Alloy Coatings by Laser Synthesis

10.1115/imece2000-2639 ◽

2000 ◽

Author(s):

D. L. Tu ◽

A. Kar ◽

X. L. Wu

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Wear Resistance ◽

Chemical Reaction ◽

Phase Interface ◽

High Fracture Toughness ◽

Transmission Electron ◽

Ni Alloy ◽

The Matrix

Abstract Titanium carbide particle (TiCp)-reinforced Ni alloy composite coatings are synthesized by laser cladding using a cw 3 kW CO2 laser. Two kinds of coatings are possible in terms of the origin of TiCp: undissolved TiCp and in-situ generated TiCp. The former originates from the TiCp pre-coated on the sample whereas the latter from in-situ chemical reaction between titanium and graphite in the molten pool during laser irradiation. For the coating reinforced by TiCp formed in-situ, the sub-micron TiCp particles are formed and uniformly distributed because of the in-situ reaction and trapping effect during rapid solidification. Graded distribution of TiCp is obtained on a macro scale. The volume fraction increases from 1.86% at the coating-substrate interface to 38.4% at the coating surface. For the coating reinforced by undissolved TiCp, analytical transmission electron microscopy (ATEM) and high resolution transmission electron microscopy (HRTEM) observations show the existence of the epitaxial growth of TiC, the precipitation of CrB and M23C6, and the chemical reaction between Ti and B elements around phase interfaces of undissolved TiCp. In the matrix near the phase interface of undissolved TiCp, the loading curve obtained by nanoindenter exhibits pop-in phenomena due to the plastic deformation of cracks or debonding of TiCp from the matrix. For TiCp generated in-situ, no pop-in mark appears, indicating high fracture toughness. Coating with TiCp generated in-situ exhibits higher hardness and modulus than the coating with undissolved TiCp at regions near the phase interface. The coating reinforced by TiCp generated in-situ also displays higher impact wear resistance and abrasive wear resistance compared to the coatings with undissolved TiCp and without TiCp respectively.

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Mechanical Properties of In-Situ Synthesis of Ti-Ti3Al Metal Composite Prepared by Selective Laser Melting

Metals ◽

10.3390/met9101121 ◽

2019 ◽

Vol 9 (10) ◽

pp. 1121 ◽

Cited By ~ 4

Author(s):

Li ◽

Liang ◽

Tian ◽

Yang ◽

Xie ◽

...

Keyword(s):

Mechanical Properties ◽

Wear Resistance ◽

Selective Laser Melting ◽

Melting Process ◽

In Situ Synthesis ◽

Metal Composite ◽

Dispersion Strengthening ◽

Laser Melting ◽

Compression Properties

Titanium composite strengthened by Ti3Al precipitations is considered to be one of the excellent materials that is widely used in engineering. In this work, we prepared a kind of Ti-Ti3Al metallic composite by in-situ synthesis technology during the SLM (selective laser melting) process, and analyzed its microstructure, wear resistance, microhardness, and compression properties. The results showed that the Ti-Ti3Al composite, prepared by in-situ synthesis technology based on SLM, had more homogeneous Ti3Al-enhanced phase dispersion strengthening structure. The grain size of the workpiece was about 1 μm, and that of the Ti3Al particle was about 200 nm. Granular Ti3Al was precipitated after the aluminum-containing workpiece formed, with a relatively uniform distribution. Regarding the mechanical properties, the hardness (539 HV) and the wear resistance were significantly improved when compared with the Cp-Ti workpiece. The compressive strength of the workpiece increased from 886.32 MPa to 1568 MPa, and the tensile strength of the workpiece increased from 531 MPa to 567 MPa after adding aluminum. In the future, the combination of in-situ synthesis technology and SLM technology can be used to flexibly adjust the properties of Ti-based materials.

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A Comparative Study on the Tribological Properties of a Cobalt-Free Superaustenitic Stainless Steel at Elevated Temperature

Metals ◽

10.3390/met10091123 ◽

2020 ◽

Vol 10 (9) ◽

pp. 1123

Author(s):

Frederic van gen Hassend ◽

Sebastian Weber

Keyword(s):

Stainless Steel ◽

Wear Resistance ◽

Elevated Temperature ◽

Superaustenitic Stainless Steel ◽

Material Loss ◽

Hardness Tests ◽

Alternative Material ◽

Wear Tests ◽

Hot Hardness

The properties of a cobalt-free cast superaustenitic stainless steel (SASS) is investigated comparatively to the commercial high-cobalt alloyed GX15CrNiCo21-20-20 (1.4957, N-155) steel regarding its global hardness and wear resistance at elevated temperature by means of in situ hot hardness tests and cyclic abrasive sliding wear tests against an Al2O3 (corundum) counter-body at 600 °C. In the aged condition, results show that the 1.4957 steel suffers a higher material loss due to brittle failure initiated by coarse eutectic Cr-rich carbides which are incorporated into a mechanically mixed layer during abrasive loading. In contrast, within the Co-free steel eutectic M6(C,N) carbonitrides are distributed more homogeneously showing less tendency to form network structures. Due to the combination of primary Nb-rich globular-blocky MX-type carbonitrides and eutectic M6(C,N) carbonitrides dispersed within an Laves phase strengthened austenitic matrix, this steel provides comparable hardness and significantly improved wear resistance at elevated temperature. Thus, it may be an adequate alternative material to commercial SASS and offers the possibility to save cobalt for future applications.

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