Varjenje z gnetenjem aluminijeve zlitine 2030

Zaradi fizikalnih in kemičnih lastnosti aluminija in aluminijevih zlitin je njihovo varjenje oteženo in omejeno na določene postopke spajanja. Eden izmed bolj primernih postopkov spajanja aluminija in njegovih zlitin je varjenje z gnetenjem. Gre za termomehanski postopek pri katerem varjenje poteka pri nižjih temperaturah, na zvar pa dodatno vpliva potisna sila, zaradi česar v zvaru dobimo dobre mehanske lastnosti. V nalogi smo raziskali vpliv različnih varilnih parametrov na kakovost zvara. Varili smo po sistemu matrike s podajalnimi hitrostmi 73, 93 in 116 mm/min in vrtljaji 750, 950 in 1180 vrt/min, ter tako dobili 9 vzorcev. Za vsak vzorec smo naredili vizualno analizo, natezni preizkus, analizo trdote, analizo mikrostrukture, analizo temperatur med varjenjem in analizo upogibnega kota. Na podlagi analiz smo ugotovili, da so optimalni parametri za varjenje podajanje 93 mm/min in vrtljaji 950 vrt/min. Pri teh parametrih je faktor ONP 10,2. Pri faktorjih ONP nižjih ali višjih od optimalnega pride do slabše kakovosti zvara, kar je lahko posledica prevelikega vnosa energije v zvar ali slabega mešanja v njem. Because of the physical and chemical properties of aluminum and its alloys, its welding is difficult and limited to certain welding processes. One of the more suitable processes for welding aluminum and its alloys is friction stir welding. It is a thermomechanical process in which welding takes place at lower temperature, and the weld is further influenced by the pushing force what leads to good mechanical properties. In this paper, we studied the influence of different welding parameters on the quality of the weld. We were welding by a matrix system with feed speeds of 73, 93 and 116 mm/min and rotational speed 750, 950 and 1180 rpm, what gave us 9 samples. For each sample we made a visual, tensile strenght, hardness, microstructure, temperature during welding and bend angle analysis. On the basis of the analysis we found that optimal parameters are welding speed 93 mm/min and rotational speed 950 rpm. For this parameters the revolution per feed (RPF) factor was 10.2. For RPF factors lower or higher than optimum, we got lower quality of the weld due to high energy intake or poor mixing within the weld.