The functionality of a prosthesis is determined by clinical procedures, the manufacturing technology applied, the material used and its strength parameters. The aim of the paper is to evaluate the static strength and fatigue strength of acrylic construction materials directly after the process of polymerisation and for aged materials. It has been confirmed that the deformation speed of the tested materials has an evident impact on their mechanical characteristics. With greater deformation speed, a consistent increase in the material elasticity was observed in static compression tests, which was accompanied by a reduction in engineering stresses at the final stage of deformation. The greatest fatigue strength was observed for Vertex. It was by about 33% greater than the strength of Villacryl – the material that has the lowest fatigue properties. The resistance of acrylic polymers to cyclic loading applied with the frequency of 1 Hz may become an indication for the selection of the material to be used in the clinical procedures in which a patient is provided with full dentures.
This paper presents the results on the effects of die-casting process on the strength parameters of castings of the aluminium AlSi9Cu3 alloy belonging to the group of EN AB-46000, made on renovated high pressure die-casting machine. Specimens for quality testing were taken from the places of the casting most loaded during the service. The aim of a research was to prove how the new die-casting process control capabilities influence on the tensile strength of the cast material defined as a value of the breaking force of the specimens. It has been found that it is possible to specify a set of recommended settings valves of second (II) and third (III) phase, which are responsible for filling the metal mould on die-casting pressure machine. From the point of view of the finished cast element, it was noticed that exceeding the prescribed values of valve settings does not bring further benefits and even causes unnecessary overload and reduce the durability of the mold. Moreover, it was noticed that reduction of the predetermined setting of the second phase (II) valve leads to the formation of casting defects again.