Tribological behaviour of plasma-sprayed WC coatings with and without laser remelting

Matéos, J.; Cuetos, J.M.; Fernández, Estéban; Vijande, R.

doi:10.1016/s0043-1648(00)00325-2

Cited by 127 publications

(43 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Improving the hardness and wear resistance of WC-CoCr by reducing homogeneity, porosity and other microstructural defects of the coatings would have good potential for tooling applications [12][13][14]. Previous work has examined the effects of laser processing parameters, including scanning velocity, on the microstructure, hardness, wear resistance and porosity of High Velocity Oxygen Fuel (HVOF) thermally sprayed WCCrC-Ni coatings [7,15]. This work showed that the laser surface hardening of WC-CrC-Ni coatings can effectively increase the hardness and reduce the porosity in the coating with a corresponding reduction in the thickness of the coating.…”

Section: Introductionmentioning

confidence: 99%

Surface modification of HVOF thermal sprayed WC–CoCr coatings by laser treatment

et al. 2010

View full text Add to dashboard Cite

ABSTRACT:In this work the affects of laser characteristics on microstructure and microhardness of high velocity oxygen fuel sprayed (HVOF) WC-CoCr coatings were investigated. The coating was deposited with a Sulzer Metco WokaJet™-400 kerosene fuel and the laser surface treatments were applied using CO 2 laser with 10.6 μm wavelength. Large variations in surface properties were produced from variation in the laser processing parameters. In total, four levels of peak power (100, 200, 300 and 350 W), four levels of spot diameter (0.2, 0.4, 0.6 and 1 mm) and three levels of pulse repetition frequency (PRF) were investigated. An initial set of tests were followed by a more detailed 3 3 factorial design of experiments. Pulse repetition frequency and duty cycle were set in order to maintain the same overlap in the x and y directions for the raster scanned sample spot impact dimensions. Overlaps of 30% were used in the initial tests and 10% in the more detailed trials. The results have shown that care must be taken to keep the irradiance at a relatively low level compared to uncoated surfaces. High irradiance can in this case result in rough and porous surfaces. Lower levels of irradiance are shown to provide more uniform microstructures, reduced porosity and increased microhardness.

show abstract

Section: Introductionmentioning

confidence: 99%

Surface modification of HVOF thermal sprayed WC–CoCr coatings by laser treatment

et al. 2010

View full text Add to dashboard Cite

show abstract

“…Regarding the small holes, droplets and bubbles present at 30 kHz and at CW mode can be attributed to the release of entrapped gas during melting. 9,10,15,17 The slow heating process allows bubbles to coalesce and escape leaving small holes and droplets on the surface. At low repetition rates, the heating rate is high, and in addition, the thickness of molten material is small ( Table I), so that bubbles do not have time to coalesce.…”

Section: Discussionmentioning

confidence: 99%

“…This process leads not only to the total elimination of the superficial porosity but also induces changes in the morphology and composition of the coatings that can enhance their wear resistance, as has already been observed in this material 7 and many others. [8][9][10][11][12][13][14] Although most of the treatments have been carried out with continuous wave (CW) lasers, some authors 10,15 have suggested the convenience of working in the pulsed mode since it would reduce the extent of the heat-affected zone beyond the layer molten by the laser beam and thus protect the bulk of the coating and the substrate from alteration. This has motivated us to undertake a study analyzing the differences between both CW and pulsed laser irradiation regimes to determine the conditions where the laser surface treatment is more effective.…”

Section: Introductionmentioning

confidence: 99%

Structural characterization of laser-treated Cr₃C₂–NiCr coatings

et al. 2001

View full text Add to dashboard Cite

The interconnected porosity of the Cr 3 C 2 -NiCr coatings obtained by high-velocity oxy fuel spraying is detrimental in corrosion and wear resistance applications. Laser treatments allow sealing of their surfaces through melting and resolidification of a thin superficial layer. A Nd:YAG laser beam was used to irradiate Cr 3 C 2 -NiCr coatings either in the continuous wave mode or at different repetition rates in the pulsed one. Results indicated that high peak and low mean laser irradiances are not good, since samples presented deep grooves and an extensive crack network. At low peak and higher mean laser irradiances the surface was molten, and only a few shallow cracks were observed. The interconnected porosity was completely eliminated in a layer up to 80 m thick, formed by large Cr 7 C 3 grains imbedded in a NiCr matrix.

show abstract

“…Reliability of a tool in the technological lines becomes the most important factor; therefore, alternative solutions are sought among the price, availability, and the relatively long tool life. Properties of the surface layer of these steels have to protect tools from deterioration of their service life, and especially they should be characteristic of abrasion resistance at elevated temperature, cyclic mechanical loads, and corrosion action of the machined material [1][2][3]. However, investigation of the possibility of improving the service properties of tool steels with the martensitic matrix by a conventional change of their chemical composition is very limited nowadays.…”

Section: Introductionmentioning

confidence: 99%

Formation of Hard Composite Layer on Tool Steel by Laser Alloying

Bonek

2016

Archives of Metallurgy and Materials

View full text Add to dashboard Cite

Investigations include alloying the PMHSS6-5-3 steel surface layer with carbide and ceramic powders WC, VC, TiC, SiC, Si3N4 and Al2O3, using the high power diode laser (HPDL). Laser treatment is especially promising for solving contemporary surface engineering problems making it possible to focus precisely the delivered energy in the form of heat in the surface layer. The structural mechanism was determined of surface layers development, effect was studied of alloying parameters, method on structure refinement and influence of these factors on the mechanical properties of surface layer, and especially on its abrasive wear resistance. The fine grained martensite structure is responsible for hardness increase of the alloyed layer. The tribological wear relationships were determined for laser treated surface layers, determining friction coefficient, and wear trace shape developed due to the abrasive wear of the investigated surfaces. Comparison of the laser treatment parameters and tribological properties of surface layer after remelting and alloying with hard particles of the PMHSS6-5-3 steel using the high power diode laser to obtain the optimum service properties is the outcome of the investigations carried out.

show abstract

Tribological behaviour of plasma-sprayed WC coatings with and without laser remelting

Cited by 127 publications

References 9 publications

Surface modification of HVOF thermal sprayed WC–CoCr coatings by laser treatment

Surface modification of HVOF thermal sprayed WC–CoCr coatings by laser treatment

Structural characterization of laser-treated Cr₃C₂–NiCr coatings

Formation of Hard Composite Layer on Tool Steel by Laser Alloying

Contact Info

Product

Resources

About

Tribological behaviour of plasma-sprayed WC coatings with and without laser remelting

Cited by 127 publications

References 9 publications

Surface modification of HVOF thermal sprayed WC–CoCr coatings by laser treatment

Surface modification of HVOF thermal sprayed WC–CoCr coatings by laser treatment

Structural characterization of laser-treated Cr3C2–NiCr coatings

Formation of Hard Composite Layer on Tool Steel by Laser Alloying

Contact Info

Product

Resources

About

Structural characterization of laser-treated Cr₃C₂–NiCr coatings