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Electron microprobe analysis of cryolite

Electron microprobe analysis of cryolite

Shock activation of [alpha]-alumina from calcinated Al-rich sludge

http://www.sciencedirect.com/science/article/B6TWH-4V0MTS0-1/2/e62b6d65e9631a4eb781069d9f088543

Mechanical characterization of composites prepared from WC powders coated with ...

In this study composite powders of WC and Ni/Fe/Cr were prepared in an innovative way, which consists of the sputter-deposition of the metallic binder onto the tungsten carbide particles. Compacts of coated powders were sintered by conventional vacuum sintering followed by hot isostatic pressing (HIP) to reach almost full densities. In order to evaluate the mechanical properties of reduced specimens size (micro...

Thin films with chemically graded functionality based on fluorine polymers and ...

Thin films of stainless steel and poly(tetrafluoroethylene) were co-deposited, by radiofrequency magnetron sputtering, in an inert atmosphere in order to produce a functionally graded material as a coating on a traditional biomaterial, where non-ferromagnetic characteristics and improved wettability must be ensured. These thin films are intended to modify the surface of SS316L used in stents, where the bulk/thi...

Surface modification of stainless steel powders for microfabrication

The current trend towards miniaturization has led to the increasing use of stainless steel powders as raw material in the manufacture small parts with complex shapes, e.g. medical devices. This paper focuses on the role of coated and uncoated low carbon stainless steel powders, having d50 = 7.3 [mu]m, normal particle size distribution and a shape factor of 1 on additive processes used in micromanufacturing, e.g...

Structural phase evolution with temperature of non-conventional particles in PIM

Some inorganic natural powders may be interesting to manufacture complex shapes by powder injection moulding (PIM). However, these powders may evolve chemical and physically with temperature during the manufacturing processes, inducing blusters and geometrical irregularities, particularly loss of circularity. These imperfections were associated to gas liberation and dimensional variations during the debinding a...

Control of eta carbide formation in tungsten carbide powders sputter-coated wit...

Composite powders of tungsten carbide with variable coating contents of Fe/Ni/Cr based alloys (1-15 wt.%) were prepared by sputtering. The coated powders have revealed a good performance to shape-forming and sintering. However, the presence of nanocrystalline coatings could enhance the formation of a brittle phase during sintering, named [eta]-phase, (M, W)6C. To investigate this effect, the powders were heat-t...

Nanostructured coated powders for structural net shape components

The specific goal of the present study is to evaluate the surface performance of thin films based on sputtered stainless steel (304 AISI) deposited on dissimilar (Cu) and similar powder materials (316 AISI) with different size distributions and shapes. The covering efficiency, the surface morphology and the grain size, and their impact on the flowability of powders, are studied. The most important role of powde...

Mullitization kinetics from silica- and alumina-rich wastes

Mullite was produced from a mixture of raw wastes with high contents of silica and aluminium hydroxides. The first were wastes from slate rocks and had muscovite, chlorite and quartz as their main crystalline phases. The second were aluminium sludges resulting from the physico-chemical treatment of the wastewaters generated by aluminium surface treatment industries. As-received raw materials were weighed to pro...