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This paper deals with a three-component aluminum alloy AlMg4.5Mn that was welded using a GTAW process in the shielded atmosphere of Ar+70%He+0.015%N2. The weld-metal toughness was evaluated at three different temperatures using instrumental Charpy pendulum impact testing to measure not only the total energy, but also the crack initiation energy and the crack growth energy. Fractographic analysis of the fracture surfaces and EDS analysis of large second-phase particles on fractured surfaces at each temperature were also carried out. Fractographic analysis at different temperatures indicated a clearly distinguishable fracture mechanism. It was inferred that the absorbed energy was closely correlated with the fracturing of surfaces. Moreover, it was concluded that with decrease in the amount of microscopic voids and dimples, the total energy absorbed also decreased.

Welding in virtual reality is an artificial, computer generated, environment where the welder is located with a goal of the successful realization of the welding process. This process should be ended with a best derived welded joint for the given conditions. The main idea of the following type of software is to focus on the training of future welders. During the training, a great amount of energy is consumed, and hazardous radiation, fumes and gasses have an effect on the health of the welder. Therefore, the application of the software for welding in virtual reality allows a great saving in material and energy, moreover, it reduces or eliminates all harmful effects of the welding process. This paper elucidates all the possibilities of the application of one software for welding in virtual reality called "Hyperwelder". The focus is the analysis of the two parts of this software that refers to the welding training, and the simulation in workshop conditions. It is indicated on the possibilities of the software, its advantages and disadvantages, and further development in the way of welding in more real working conditions. Summarizing all the benefits that welding in virtual reality brings, this way of training will most certainly become obligatory in every training process.

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Kvalitet zavarenih spojeva zavisi od mnogobrojnih konstrukcionih i tehnoloških faktora. Kod većine zavarenih spojeva ne postoji dovoljno dokaza da je proces zavarivanja sproveden koristeći parametre propisane tehnologijom zavarivanja. Odstupanja od propisanih parametara mogu dovesti do pojave različitih tipova nesavršenosti u zavarenom spoju i uticati na mikrostrukturu i mehaničke karakteristike materijala, što skupa može ugroziti integritet konstrukcije. Tokom protekle decenije intenzivno se radilo na razvijanju sistema za praćenje i kontrolu parametara zavarivanja, koji se zasnivaju na merenju određenih fizičkih veličina u realnom vremenu. U slučaju odstupanja od vrednosti parametara propisanih u tehnologiji zavarivanja ovi sistemi šalju odgovarajuća upozorenja operateru i omogućavaju da se momentalno reaguje u cilju korekcije parametara, čime se direktno utiče na obezbeđenje kvaliteta zavarenog spoja. U radu su prikazane osnovne mogućnosti ovih sistema i prednosti njihovog korišćenja u industriji.