The coating on the 22MnB5 steel is intended to protect it against oxidation during the forming process. This steel is hot-pressed. A preheating before the pressing and subsequent hardening in the tool affects the properties of the AlSi coating. This study summarizes the results of investigating the effect of heat treatment parameters on the formation of intermetallics in the AlSi coating. The chemical analysis of the coating was performed by the EDX and EBSD method and the mechanical properties were determined by the Hysitron TI 950 TriboIndenter™ system. The result of this study is that, due to a diffusion during the heat treatment, the brittle coating was transformed into a tougher phase.

The paper deals with a machining of polymeric composite materials with a reinforcement based on a waste from a coconut processing, i.e. a coconut shell by means of an unconventional technology, i.e. a water jet (WJ). These composite systems are desirable in the material engineering. Not only the research of their subsequent mechanical properties is important, but also searching for effective ways of machining and dividing to required shape and size. The composite material was tested in a form of boards made by means of a vacuum infusion. The aim of the research is to study an influence of the abrasive water jet and water jet at its impact on a surface of the machined polymeric composite material. The research was proved on CNC cutting machine AWJ CT 0806. Cutting conditions, i.e. various traverse speeds 50, 100, 250, 500, 750 and 1000 mm/min, an influence of cutting by the water jet with abrasive particles and without them on an integrity of the tested material and the surface topography were evaluated within the research. A surface analysis is also evaluated by means of a scanning electron microscopy (SEM) depending on a traverse speed and a mass flow of the abrasive grains.