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Si3N4/hBN composites were fabricated by hot isostatic pressing at 1700°C/3h with 1, 3 and 5 wt. % micro-sized or nano-sized hexagonal boron nitride particles added to silicon nitride matrix. An indentation quench test method was used for estimation of thermal shock resistance of monolithic Si3N4and Si3N4/hBN composites. Thermal shock resistance of the composites increased with the increase of size and volume of hBN particles. The critical temperature difference for the composites with micro-sized hBN was significantly higher (over 900°C) compared to the monolithic silicon nitride (580°C).

The aim of this work is indentation study of local mechanical properties of Cu-22Zn-4.6Al alloy, which has significant shape memory effect after quenching from dual α + β phase region. The study was carried out on the samples with thermoelastic and non-thermoelastic martensite in the structure, which were obtained by quenching from various temperatures. A different behavior concerning mechanical properties measurements of α phase and β phase transformed to martensite after quenching from various temperatures was found out. It was observed almost no change of mechanical properties of α phase, whereas indentation hardness HIT and indentation modulus EIT raised with increasing quenching temperature. Also some serious differences were observed at indentation test of thermoelastic and non-thermoelastic martensite.

Several bone cements were prepared in two ways of mixing (manual and vacuum bowl). Wear behavior, friction coefficient were studied by ball on disc method. Nano-hardness and Young`s modulus was studied by instrumented indentation. Obtained results were summarized by taking into account their way preparation, antibiotics content and testing conditions. There was found no significant time dependence of saline acting on Young`s modulus and nano-hardness values. Friction coefficient in saline was less than half in compare to dry sliding conditions