The paper presents our actual knowledge and experience in joining dissimilar materials with the use of friction welding method. The joints of aluminium and aluminium alloys with the different types of steel were studied. The structural effects occurring during the welding process were described. The mechanical properties using, for example, (i) microhardness measurements, (ii) tensile tests, (iii) bending tests, and (iv) shearing tests were determined. In order to obtain high-quality joints the influence of different configurations of the process such as (i) changing the geometry of bonding surface, (ii) using the interlayer, or (iii) heat treatment was analyzed. Finally, the issues related to the selection of optimal parameters of friction welding process were also investigated.

StreszczenieW artykule przedstawiono tendencje rozwojowe lutowania miękkiego i twardego. Zaprezentowano perspektywiczne kierunki oraz obszary badawcze, które w ostatnich latach dynamicznie ewoluowały. Opisano charakterystyki materiałów, których lutowanie jest problematyczne. Udowodniono, że zastosowanie nowoczesnych technik oraz odpowiedni dobór materiałów dodatkowych, umożliwia ich jakościowe wytwarzanie. Przedstawiono rozwój systemów kontrolnych i stopnia zautomatyzowania stanowisk lutowniczych. Wskazano na dynamicznie rozwijające się metody lutowania, proponując przy tym alternatywne źró-dła ciepła.Słowa kluczowe: postęp w technologiach lutowania; nowoczesne metody lutowania; jakość złączy lutowanych; automatyzacja lutowania AbstractDevelopment trends of soldering and brazing technologies were presented in this paper. Perspective directions and research areas, which in recent years evolved rapidly, were introduced. Characteristics of materials, which soldering and brazing is problematic, were described and it was proven that use of modern techniques and appropriate selection of additive materials, enables their qualitative manufacture. Development of control systems and automation degree of soldering and brazing stations were presented. Rapidly developing methods of soldering and brazing were pointed out, giving an idea of alternative heat sources.

The article presents an analysis of the Cold Metal Transfer (CMT) method, including the process, advantages and application of the method. The joints made with low energy CMT method and classic MAG method were also compared. The paper presents the results of non-destructive penetrant tests of welded joints made of steel in the S235JR grade. Microscopic observations were made using optical microscopy and the hardness was measured in accordance with PN-EN ISO 6507-1:2007. The test results confirmed that the CMT process allows for the production of high-quality joints and a narrow heat-affected zone compared to the classic MAG welding method, and also provides good mechanical properties and elimination of spatter.

W artykule przedstawiono możliwości wykorzystania mikroskopii akustycznej do oceny niezgodności połączeń zgrzewanych. W ramach prac badawczych wykonano połączenia zgrzewane dwóch gatunków blach aluminowych EN AW5754 H24 oraz EN AW6005 T606, które następnie zostały poddane badaniom nieniszczącym z wykorzystaniem mikroskopii akustycznej oraz konwencjonalnym badaniom niszczącym z wykorzystaniem tradycyjnych technik przy użyciu mikroskopii świetlnej.

The subject of the research was the installation of a water steam used in the chemical industry. Penetration tests revealed an extensive network of cracks on the surface of steel and welds. Metallographic studies, chemical composition analysis, EDX anal-ysis were performed. Thermal treatment of steel was carried out and microhardness measurements were made. The results of the tests showed that stress corrosion was the main reason for the occurrence of cracks.