The article presents results of tests performed to determine the noise level in ultrasonic Phased Array testing. The tests, involving non-alloy steel S355 and austenitic steel X5CrNi18-10, were carried out applying a frequently used test configuration and 16-element 5 MHz array probes having an aperture of 10 mm ×10 mm. The obtainment of a differentiated structure, i.e. characterised by various grain sizes, required the performance of special heat treatment processes. Metallographic tests, concerning both steel grades, were performed to quantify the grain size. Specimens containing artificially made SDH Ø3 cylindrical reflectors and spherical reflectors having various diameters were made of the material prepared in the above-presented manner. The tests also involved amplitude measurements and the identification of the noise level of the reflectors. The test results enabled the quantitative determination of the signal-noise ratio, affecting the detection of low-amplitude indications.

Abstract:The article aims to present the manner in which welding processes are modelled using dedicated software programmes, provides examples concerning applications of various heat sources and indicates the necessity of performing tests aimed to increase the consistence of simulation results with those obtained in experimental verification.

Abstract:The article aims to present a number of factors affecting the geometrical shape of a liquid metal pool when making welded joints, i.e. factors increasing or decreasing a heat input including the density and efficiency of welding power sources, stirring efficiency, tungsten electrode tip point, heat flow in a material being welded, cooling rate and linear energy supplied to a joint.

Abstract:The article presents imperfections tested using penetrant methods. The research described in the article was concerned with imperfections regarded as the most hazardous, i.e. cracks. The tests involved the formation of natural cracks in structural steel S355J2C+N. The cracks were measured in terms of their width and the roughness profile of their surface. The research involved a number of penetrant tests aimed to determine how a given factor (crack width or crack surface roughness) affected the time of development in penetrant tests of joints made in structural steel.