Experiments to directly bond AlN with Cu were conducted for different pre-treatments of the bonded components. AlN substrates were implanted either with oxygen, or titanium or iron ions at low (15 keV) or high (70 keV) energy, or thermally oxidized. Some Ti-implanted samples were also thermally oxidized. The copper component was annealed and thermally oxidized. The best results, with respect to the bond shear strength, were obtained for low-energy implantation of oxygen and titanium.
This paper deals with the development of magnetoactive elastomers (MREs) based on the carbonyl iron particles-filled polyurethane resin. Their stiffness can be changed easily by magnetic field. Such a property can be useful in construction of active vibration damping structural elements.
For the needs of numerical modelling methods validation the elementary case of the two magnetic particles was investigated experimentally.
Special “macro samples” were prepared with pairs of ferromagnetic particles of spherical shape of diameter of 12.7 mm. They provided easy observations and measurements. The gap distance between particles was established on the level of ¼ of the diameter.
After application of the magnetic field particles started to attract each other like magnetic dipoles.
The mutual displacement of the dipoles was recorded in function of the magnetic field intensity, which was varied in the range100÷300 [mT].
The deformation field was also obtained from the digital image processing (DIC).
Then the experiment was simulated numerically with the use of the 3D FEM models. The dipoles were loaded by forces which were increased gradually until displacements reached values that were measured experimentally. Calculations were performed on the MSC Patran-MARC platform. The Neo-Hookean material model was used to describe properties of the resin matrix. Magneto-mechanical coupling was taken into consideration with the use of an iterative method.
The results of calculations were compared with the experimental results. The validation of the base modelling concept was successfully completed.
In the field of numerical research there are various approaches and methods for structures of porous materials modeling. The solution is the use of fractal models to develop the porous structure. In the case of modeling the geometry of natural (random) materials, there is a problem of compatibility of the FE model geometry and real one. This is a source of differences between the results of calculations and experimental ones. Application of 3D printing technology will allow to receive a real structure in a controlled manner, which exactly reflects the designed structure and is consistent with the geometry of the numerical model. An experimental research on the standard samples made of photopolymer resin using 3D printing technique was presented in the paper. The aim of the research was to determine the base material properties and, consequently, to select the constitutive model, which is necessary to carry out numerical analyses.
The method of pipeline inspection data usage for needs of numerical analysis of technical condition of pipeline is considered. A real crude oil pipeline was taken into considerations to make numerical assessment of stress state in case of large deformations which were measured by an intelligent caliper inspection tool. The pipeline was rested on concrete supporting blocks in a boggy terrain. The tool detected very large deformations of the pipe in the areas of these supports which were caused by washouts. Data from the tool were processed into the format readable for MSC/PATRAN-graphical pre-processor of the computational system MSC/NASTRAN based on the Finite Element Method – FEM. Then a mesh of discrete model was generated by means of MSC/PATRAN.
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