International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

Tribological tests were carried out on four Ti-TiC composite samples to investigate the tribological behaviour of this alloy and the influence of sintering parameters on it. The samples were sintered by SPS using a high voltage electrical discharge. The general sintering parameters of the samples are temperature – 1100°C, heating rate – 10 °C/s, heating time – 3 min, initial pulse current – 260 A, maximum pulse current – 500 A. The different parameters are as follows: the number of pulses used for the first and fourth samples is 1000, for the second and third samples 2000; for the first and second samples a 1 electrode system was used, for the third and fourth samples a 3-electrode system. The hardness of the samples was measured using the Vickers method. The first specimen, sintered with 1000 pulses and 1 electrode system, has the highest hardness of 456.84 HV10. This is related to the fact that this sample showed the best tribological properties: the lowest friction coefficient of 0.39 and the lowest wear rate of 6.4∙10-4 mm3/Nm. It was observed that the samples sintered with 1000 pulses had lower average coefficients of friction: the average coefficients of friction of the first and fourth samples are 0.39 and 0.48 respectively, while the second and third samples are 0.54 and 0.51 respectively. The friction and wear characteristics of the first specimen, which has the best tribological properties, were compared with those of a Ti-Al-V alloy widely used in aviation. The Ti-TiC sample showed a better friction coefficient and better wear characteristics.

Phase transformations in metals have a major influence on the material behaviour in several common engineering applications. Steels exhibiting enhanced response to transformation-induced plasticity (e. g. high strength TRIP-steels for automotive production) are examples of the important role martensite formation can play. An externally stressed specimen in the process of a phase transformation may show a significant nonlinear behaviour, which is known as transformation plasticity. Even under an externally applied load stress with the corresponding equivalent stress being small in relation to the “normal” yield stress of the material, plastic deformation occurs.
An aim of a research was to determine relaxation and transformation plasticity properties of alloyed tool steel while is tempered at elevated temperatures and for different tempering duration.

An aim of a research was to determine the reasons of fracture of aluminium alloy components used for spinning of chemical fibres and to improve spinning process by selecting material with better performance.

Analysis of PowerCore automotive air filter was made and development of new alternative air filter was performed by increasing surface area of filtering material. New shape of construction of air filter was suggested by introducing double-layer filtering material. It was determined that effective surface area of the new design of air filter was increased 1.5 times comparing with the patented PowerCore item of the same size. Efficiency and strength of the new design air filter was evaluated calculating air flux rates, deformations and displacement in SolidWorks environment.