In the thesis, we studied the basic mechanical properties and dimensional stability of 3D printed samples from four different materials in changing climatic conditions. We used pure PLA and three wood-plastic composites, with different wood ratios (up to 40 %, 15 %, and 25 %). The samples were first moistened, then dried and their dimensional changes monitored. With the obtained information on selected materials, we started preparing and making samples from two different materials (PLA and wood-plastic composite) in different layer thicknesses in the composite sample. To make it easier to see how our tests will respond, we performed computer simulations in SolidWorks and selected the optimal combinations of layer thicknesses and materials to achieve the greatest shape changes in changing climatic conditions. In all cases, the PLA material was selected as the passive layer, and the material with the 15 % and 25 % wood dust content was chosen as the active layer. In the case of such printed elements, we determined their response to exposure in a humid climate (RZV 88 %). By combining two materials in one element and exposing these elements in a humid climate, we triggered an autonomous response of the systems (samples were automatically curved. The samples, which had material with a higher proportion of wood in the active layer, changed the shape – curved the most, and the size and velocity of the deformation are also influenced by the ratio between the thickness of the PLA layer and the wood-plastic composite.
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