This paper addresses an innovative syntactic foam produced out of metal powder (Fe), fly ash cenospheres (CS) and clay ceramic syntactic foams composite material (CM). Due to the low density of CS (bulk density - 0.38 g/cm3), the average density of these foams is about 2.6-2.9 g/cm3. It was found that CS undergoes phase transformation during thermal treatment at a temperature of 1200°C. Microstructural observations reveal a uniform distribution of CS and Fe particles in the composite. Compressive strength, and friction coefficient of obtained Fe/CS CM are in the range between 149 - 344 MPa and 0.15 - 1.1, respectively. Dependence of compressive strength on firing temperature is demonstrated exhibiting the maximum at 344 MPa; however, dependence of coefficient of friction on a material properties, obtained at different firing temperature exhibits the minimum value of 0.15 at the firing temperature of 1150 °C. The obtained syntactic form was shown to be a candidate for wear resistant applications.

This work focuses on clay ceramic hollow spheres (CCHS) preparation using Liepa clay and sacrificial template method in a lab scale device and testing of their properties. Water retention and compression strength were investigated in order to found out if obtained CCHS can be used as an additive for improving soil resilience.The synthesis and characterization of CCHS using expanded polystyrene spheres (EPS) as sacrificial template is presented. CCHS were fired at five different temperatures and their compressive strength, water retention, bulk density, material density, water absorption, phase composition, surface morphology, porosity using hydrostaticweighing and BET nitrogen adsorption methods, were determined.Study of clay ceramic hollow sphere structure and surface morphology revealed that all samples have spherical shape. These spheres have several pronounced protrusions from the granulation process. Clay ceramic hollow spheres have porosity rate of 21 - 36% and a water absorption rate of 15 -33%. The highest rate of porosity and water absorption was observed for hollow spheres fired at 1050°C.The increase of clayceramic hollow spheresfiringtemperature led to decrease of specific surface area-thehighestvaluewas observed at950°C and the lowest at 1150°C. The bulk density increased at 1150°C.Mechanicalstrength test of ceramic hollowspheres(HS)revealedthat with the increase of scorchingtemperature the compression strength of the spheres increasedas well.The sphere hollowshadpractically globular shape with the averagewallthickness of0,6 mm, whichcomprises10-13% ofthe outer diameter.The obtained clay ceramic hollow spheres are proposed as water retention agent.

This Current paper reports the research conducted at Riga Technical University and Rezekne Higher Education Institution on the development of sorbent material, which is made of closed hollow microspheres possesses ferromagnetic properties, with a large specific surface. A review and comparison of existing sorbents for oil products collection are presented. The manufacturing process of proposed sorbent are described. The structure and morphology of obtained composite sorbent are discussed. It was found that proposed sorbent allows an efficient and safe way for surface water cleaning contaminated by spilled oil products. In particular, it shows a storing effect on a thin oil film (1-2 mm). Adsorption capacity to motor oil is investigated and compared with other magnetic sorbents on metal powders base. Newly proposed sorbent demonstrates a significantly higher adsorption capacity comparing to iron powders. Sorbent saturated by spilled oil can be evacuated by means of magnetic (or electromagnetic) captures.

A waste of composite material (CM), containing boron-tungsten fibre and aluminium matrix (CM Al-W-B) is investigated. A method of grinding has been used for processing of Al-W-B CM waste. This method has been carried out in several stages in order to obtain a powder with determined particle size. The milled material contains aluminium matrix alloy, boron and tungsten. The morphology of CM Al-W-B particles is described. The mechanism of disintegration and relationship between energy spent for disintegration, and a degree of milling of CM Al-W-B powder, are described. Possible applications of Al-W-B composite powder as a source material for obtaining a new composite ceramics by self-propagating high-temperature synthesis (SHS) are noted.

The dynamic alloying of aluminum and its alloy with a high-speed stream of silicon carbide (SiC) particles simulates the effect of a stream of cosmic dust on spacecraft materials. The study showed a structure change in the volume of aluminum and its alloy and the formation of new structural elements. The transformation of the structure during dynamic alloying leads to a change of the composition and mechanical properties of the matrix material.