The cold gas dynamic spray process, or cold spraying (CS), represents a radical departure from conventional thermal spray (TS) methods in that the deposition process relies purely on kinetic energy rather than on a combination of thermal and kinetic components. A potential advantage of this process over TS is the ability to generate dense coatings retaining initial material chemistry and phase composition with a very little oxidation. Also, low temperature process (no bulk particle melting) eliminates solidification stresses and enables thicker coatings. However, hard brittle materials like ceramics can not be sprayed without using ductile binders. In this study, magnetic alloys such as FeSiBNbCu also called Finemet and FeSiBNbCu-Al with various percentages of Aluminum coatings were synthesized using cold spray technique in order to produce ferromagnetic materials. Ultra-fine grain coatings were obtained using FINEMET nanostructured powders mixed with Aluminum as ductile binder in order to improve adherence. Magnetic measurements revealed a soft magnetic character for all the powders and the coatings. 25% of Al was considered as ideal to produce a homogenous coating with suitable magnetic properties.

The emergence of lanthanum silicate as an electrolyte is required to accelerate the development of synthesis techniques for intermediate temperature solid oxide fuel cells (ITSOFCs). Apatite-type oxide powders of La 10 (SiO 4 ) 6 O 3 have been elaborated through atmospheric plasma spraying (APS) using micro-scale mixtures of La 2 O 3 and SiO 2 powders. Granulometer and scanning electron microscopy analyses have indicated the result of high temperature reaction and rapid solidification in the evolution of multi-scale microstructure.

Although it is widely used prior to the spraying stage to eliminate the surface contaminants and to improve the splat contact with substrate, a preheating operation should be precisely controlled to keep the metallic substrate away from an excessive oxidation. In most cases, the oxide scale can deteriorate the interface adhesion. A nanosecond pulsed laser treatment is a powerful tool to remove the surface oxide layers. It is also the fundamental principle of the PROTAL process that combines a laser surface preparation and the thermal spraying process. In this paper, a nanosecond pulsed laser was used to remove the thermally induced oxide while keeping the advantage of preheating. It is shown that the particle splashing was suppressed and the deposit adhesion was significantly improved resulting from the laser cleaning effects. The mechanism of oxide removal is also investigated.

Amorphous PEEK coating was prepared on Al substrate, employing flame spraying technology. The amorphous coating was subjected to annealing treatments under different conditions. Both differential scanning calorimetry (DSC) and wide angle X-ray diffraction (WAXD) analysis revealed that the isothermally treated coating exhibited semi-crystalline structure. Coexistence of double crystal entities in semi-crystalline PEEK coating was deduced from the results obtained by DSC and WAXD measurements. Annealing temperature and holding time under this temperature affect the morphology of the minor crystal entity which is metastable. The mechanical properties of the isothermally treated coating were investigated considering coating microhardness and friction and wear properties. The variations of the coating mechanical properties were correlated with the modifications in the coating structure induced by the different annealing conditions.