Wear resistance of materials in very aggressive environment of different industrial sectors like drilling, mining, cutting, etc, appears to be critical and many efforts have been made to limit the major economic loss that represents a broken or damaged tool. The objective of the CLADIAM project (G5ST-CT-2002-50179) is to develop a cladding technique to coat complex parts based on an innovative cladding material composed of diamond pellets and cast spherical tungsten carbide particles using an automated high power diode laser (HPLD) equipment. The result of these two and a half years of work has led to the finalization of following techniques: A pelletizing alloy that takes into account the constraints of laser cladding, Enrobing of diamond particles to avoid their damage, An industrial technique, technically and economically efficient, of laser cladding that allows the realization of complex shapes. The combination of a new technique of wear and abrasion tests has led to the characterization of the obtained cladding. The results have been compared with the tests on industrial parts in severe and even extreme wear conditions. The development of this new cladding technology has been possible thanks to the use, the characterization and the optimization of specific cladding nozzles associated with the special beam of high power diode laser. The results obtained are very encouraging and open the doors to new claddings that combine the specific advantages of diamond and tungsten carbides for the nature of cladding, but also the fineness of the structure, the improvement of behaviour in wear conditions, the small thermal impact of the parts, some of the well known advantages of laser cladding.

In many industrial processes, metallic materials are subjected to high temperature corrosion and aggressive forms of erosion. Such conditions occur especially in thermal energy advanced systems using tube bundles of fluidised bed boilers. For these types of plants, availability and low costs determine the choice of materials and in most cases this choice is not optimised for middle or long-term behaviour. Moreover, few data exist to estimate material lifetime under such aggressive conditions. Such is the case for low carbon steel grades which constitute the basic materials for these plants. New FeAl intermetallic alloys have been developed in the framework of a European collaboration, and it has been seen that these materials have good corrosion and erosion resistance properties at high temperature. Heat exchanger tubes in low carbon steel have been coated by thermal-spray then tested in a new industrial plant burning a very poor fuel (coal residues). After 5000 hours of operation in a rich erosive high temperature environment (850-900°C), no significant wear was observed on coated tubes whereas the other tubes, without protection, showed an appreciable diameter reduction.