High Power Diode Laser Cladding of Wear Resistant Metal Matrix Composite Coatings

Abstract

The paper describes the application of high power direct diode laser (HPDDL), with a rectangular laser beam spot of size 1.8x6.8 mm, for the cladding of Ni-based alloy (NiSiB)+WC composite coatings. The laser cladding process was carried out with a direct injection of cladding powder into the melt pool. The influence of parameters, such as laser power beam (heat input) and WC particles size in the cladding powder on the coatings microstructure and wear properties was investigated. The microstructure and morphology of the coatings were assessed by optical and scanning electron microscopy. Wear properties of the coatings were investigated using abrasive and erosive wear tests. The results showed that a proper selection of laser cladding parameters provides non-porous coatings with excellent metallurgical bonding and a homogeneous distribution of WC particles. The dissolution of WC particles increases with the size of WC particles decreasing in the cladding powder and increasing the laser power level (heat input). The coatings containing WC particles in size range of 100-200 µm provide the highestwear resistance under erosive and abrasiveconditions.

Investigation studies involving wear-resistant ALD/PVD hybrid coatings on sintered tool substrates

“…In order to improve the operating properties of products, various surface-machining technologies are applied. [2][3][4][5][6] The advantages arising from the application of PVD coatings on cutting tools such as a high microhardness and resistance to abrasion, a low friction coefficient of the tool covered with the coat, the resistance to oxidation or to the formation of build-up edges on the tool, combined with the possibility to machine materials without liquid cooling lubricants are important contributions advocating the development of this technological field. However, in order to improve the desired properties of PVD coatings, one of the basic properties must be taken care of, which is the adherence to the substrate.…”

Use of micromachining to shape the structure and electrical properties of the front electrode of a silicon solar cell

“…Therefore, research studies are being carried out to find new solutions involving the production technology and indispensable tools used for this purpose, aiming to raise the cell efficiency with the minimum reduction of the material consumption. 1,[4][5][6][7][8] One of such emerging production operations involving photovoltaic cells is the deposition of electrical contacts. As it has been found by numerous research studies, the electrode coating should satisfy different requirements to ensure a low resistance of the interface zone between the electrode and the substrate.…”

Erosion wear resistance of titanium-matrix composite Ti/TiN produced by diode-laser gas nitriding

“…1,17 For example, the engines of planes, helicopters, and other aircraft, as well as rocket engines are often subjected to severe erosion from sand and dust particles, drops of rain, or other solid and hard particles in flight and also during manoeuvres at the airport or landing pad. [18][19][20] However, titanium alloys, and particularly pure titanium, do not possess high resistance to erosive wear because of the relatively low surface hardness. [1][2][3][4][5][6] Therefore, various methods to modify the surface of the titanium alloys are used in industry, and also new methods and techniques are being developed.…”