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This chapter of the book presents the basis of classical powder metallurgy technologies and discusses powder fabrication, preparation, preliminary moulding, sintering and inish treatment operations. A general description of the materials and products manufactured with the classical powder metallurgy methods is presented. New variants are characterised along with special and hybrid technologies inding their applications in powder metallurgy. Special atention was drawn to microporous titanium and to TiAl6V4 alloy fabricated using hybrid rapid manufacturing technologies with selective laser sintering/selective laser melting (SLS/SLM) used for innovative implant scafolds in medicine and regenerative dentistry. Laser deposition, thermal spraying and detonation spraying of powders are also discussed as special methods in which powders of metals and other materials are used as raw materials.Keywords: powder metallurgy, moulding, sintering, special power metallurgy methods, additive manufacturing, near net shape, implant scafolds, laser deposition of powders, thermal spraying and detonation spraying of powders

The aim of this work is to determine the effect of a reinforcing phase and manufacturing conditions on the structure and properties of newly developed nanostructural powders of composite materials with the aluminium alloy matrix reinforced with natural halloysite nanotubes. Composite materials were manufactured employing as a matrix the air atomized powders of AA 6061 aluminium alloy and as a reinforcement the halloysite nanotubes. Composite powders of aluminium alloy matrix reinforced with 5, 10 and 15 wt.% of halloysite nanotubes were fabricated by high-energy mechanical alloying using a planetary mill. Elaborated composite powders were characterized for their apparent density, microhardness, particle size distribution and microstructure. A structure of newly developed nanostructured composite materials reinforced with halloysite nanotubes prove that a mechanical alloying process allow to improve the arrangement of reinforcing particles in the matrix material. A homogenous structure with uniformly arranged reinforcing particles can be achieved by employing reinforcement with halloysite nanotubes if short time of mechanical alloying is maintained thus eliminating an issue of their agglomeration.

The purpose of this research paper is focused on the high speed steel surface layers improvement properties using HPDL laser. The paper present laser surface technologies, investigation of structure and properties of the high speed steel alloying with carbides using high power diode laser HPDL. Investigation indicate the influence of the alloying carbides on the structure and properties of the surface layer of investigated steel depending on the kind of alloying carbides and power implemented laser (HPDL). In the effect of laser alloying with powder of carbides occurs size reduction of microstructure as well as dispersion hardening through fused in but partially dissolved carbides and consolidation through enrichment of surface layer in alloying additions coming from dissolving carbides. Introduced particles of carbides and in part remain undissolved, creating conglomerates being a result of fusion of undissolved powder grains into molten metal base. The structural mechanism was determined of surface layers development, effect was studied of alloying parameters, gas protection method, and thickness of paste layer applied onto the steel surface on structure refinement and influence of these factors on the mechanical properties of surface layer, and especially on its hardness, abrasive wear resistance, and roughness. It has the important cognitive significance and gives grounds to the practical employment of these technologies for forming the surfaces of new tools and regeneration of the used ones.

The purpose of this work was to elaborate the method of manufacturing of composite materials based on porous mullite preforms infiltrated by AlSi12 aluminium alloy. The process of manufacturing the metal matrix composites by pressure infiltration is the subject of many scientific studies because it is characterized by high efficiency and allows for accurate mapping of elements of shape and surface of elements, while the structure and properties of the composites are determined by ceramic skeletons. The eutectic aluminium alloy AlSi12 was used as a matrix while as a reinforcement were used ceramic preforms fabricated by sintering of halloysite nanotubes (HNT) powder with an addition of carbon fibres as pore forming agents. The observations of the structure were made on the light microscope and in the scanning electron microscope. The developed technology of manufacturing of composite materials with the pore ceramic mullite infiltration ensures the expected structure and can be used in practice. The composite materials made by the developed method can find application as an alternative material for elements fabricated from light metal matrix composite material reinforced with ceramic fibrous preforms.

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