The purpose of this research was to analyze polymer materials based on mechanical properties and geometrical parameters, such as the smallest material deviations and the best printing texture after three-dimensional (3D) printing in two methods of Material Jetting technology: PolyJet and MultiJet. This study covers checks for Vero Plus, Rigur, Durus, ABS, and VisiJet M2R-WT materials. Thirty flat specimens were printed both for 0 and 90 raster orientations. Specimen scans were superimposed on the 3D model from CAD software. Each of them was tested, paying attention to the accuracy and the layer thickness effect of printed components. Then, all specimens were subjected to tensile tests. The obtained data—Young’s modulus and Poisson’s ratio—were compared using statistical methods, focusing on the two most important parameters: the isotropy of the printed material in two directions and the characteristics close to linear. It was found that unitary surface deviation with general dimensional accuracy equal to ±0.1 mm was the common feature of printed models. Some small areas had lower accuracy depending on the material and printer device. Rigur material obtained the highest mechanical properties. Dimensional accuracy in Material Jetting technology as a function of layer parameters such as layer thickness and raster orientation was checked. The materials were checked in terms of relative isotropy and linearity. Additionally, similarities and differences between PolyJet and MultiJet methods were covered.
Turbine guide vanes are among the most critical and complex turbine parts. As an entire engine comprises a significant number of vanes, simplification of the measurement process translates into overall time and money savings. The key to simplification is to define critical areas for inspection, which enables relaxation of strict inspection standards in all areas of stable process manufacturing. The method described herein can help engineers to achieve savings in inspection time and cost, at the same time ensuring the correct shape of vanes as the approach used in this work places great emphasis on correlations between measurements, working conditions, and manufacturing abilities. Another element of the novelty of this approach is an atypical hybrid convention for the crossing of vertical and horizontal inspection paths, assuring a correlation between the measured sections. Although this novel approach was used to measure the geometry of a cast turbine guide vane, it can be easily implemented to measure the geometry of any other element of complex shape.
1 September 2017 in Archive of Mechanical Engineering
The aim of the paper is to validate the use of measurement methods in the study of GFRP joints. A number of tests were carried out by means of a tensile machine. The studies were concerned with rivet connection of composite materials. One performed two series of tests for two different forces and two fibre orientations. Using Finite Element Method (FEM) and Digital Image Correlation (DIC), strain maps in the test samples were defined. The results obtained with both methods were analysed and compared. The destructive force was analysed and, with the use of a strain gauge, the clamping force in a plane parallel to the annihilated sample was estimated. Destruction processes were evaluated and models of destruction were made for this type of materials taking into account their connections, such as riveting.
1 November 2013 in Composites Science and Technology