In the experimental mechanics wide variety of optical methods including measurement of deformation at reduced length scales using combination of computer vision and scanning electron microscopy (SEM) have been recently applied. One of suitable methods for in-plane measurement of displacements and deformations in the micrographs obtained by SEM is the 2D digital image correlation. In contrast to images obtained in visible spectrum by classical optical devices temporally-varying distortions known as drift distortion are present in the SEM micrographs. These distortions are caused by positional...
The diagnostic catheter is an intravascular catheter, which is usually used to inject the contrast media and/or fluids to the body. The cardiovascular system contains tight angulations in the tortuous vessels which can cause device failure. In this study the flexibility of one diagnostic catheter was investigated according to the Food and Drug Administration’s recommendation. The catheter was bended around 16 gauges with different radius. The radius decreased from 10 mm to 2.5 mm in 0.5 increments. 9 bending points were selected on the diagnostic catheter: from 120 mm to 280 mm with 20 mm...
Tungsten is a promising candidate material for use in the tokamak device aimed at future production of nuclear fusion power. Here, tungsten is intended for the application in the part called first wall, with the function of a heat-resistant plasma facing armor. In the present work, two fractions of tungsten powder (2 and 4 µm) were used to prepare two consolidated samples by spark plasma sintering (SPS), using a combination of pressure, temperature and electric power. This sintering technique produces samples of near theoretical density which is positive for the application. Tungsten...
In the article is presented the various types of belt conveyors monitoring systems. In the world there are plenty types of such kind of monitoring systems. Some of them use visual systems, others use X-ray or mechanical contact with the belt or belt equipment. In the article are shown the advantages and disadvantages of each inspection system. There are also shown the typical use of the conveyor belt systems and monitoring systems. The monitoring systems are obliged to control surface damage, steel cord defects, splice deterioration, tracking errors and monitor the state of glued and steel...
Study provides preliminary results of experimental study of tile grout material behavior. Experiments were performed with the use of microCT, three point bending test and methods for chemical analysis. It was proven that material behave very elastic and the suitability of the combination of used methods.
The detailed progress to date of new measuring method for determining properties of pavement surface (macrotexture) is presented in this paper. The method is based on non-contact 3D scanning and subsequent evaluation of the scanned images. The measuring metric and the basic measuring plate were designed for this method. Now, it is supposed to solve data processing (point cloud filtration) and find a suitable statistical method for it. Application of approximation function using spline function by the method of least squares is presently tested.
Porous metals and particularly aluminium foams are attractive materials for crash applications where constructional elements have to be able to absorb considerable amount of deformation energy while having as low weight as possible. Compressive behaviour for medium impact velocities can be experimentally assessed from a series of drop-tower impact tests instrumented with accelerometer and high-speed camera. However to predict such behaviour a proper modelling scheme has to be developed. In this paper drop-tower impact tests of Alporas aluminium foam were used for development of a material...
We present a device for measurement of surface reflectance in dependence on incidence angle and reflectance angle. This measurement enables us to quantitatively determine how much the surface is glossy or matt. The device is programmable, which enables us to choose non-equidistant steps of angles, and study special situations more in detail. It can be used for monitoring of material weathering or other types of degradation as weathering usually causes that the surface becomes more matt.
Endovascular stents such as coronary stents can be used for the treatment of atherosclerosis. If the narrowing involves a main vessel and a side branch as well, physicians have to use bifurcation stenting technique. Bifurcation lesions constitute nearly 15 % of all percutaneous coronary interventions (PCI), so the investigation of bifurcation stenting methods is very important. This article introduces a simple method to measure side branch access and related functional stent properties in the case of stent-balloon technique. With this method we can tell if bifurcation stenting is possible or...
This paper deals with calculation of fibre orientation distribution (FOD) in fibre reinforced composite. The calculation was based on image analysis algorithm applied on image acquired by scanning electron microscope. A composite with oriented fibres was selected to be enable calibration of the algorithm by comparison of the obtained results with FOD declared by the manufacturer.