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U radu su predstavljeni rezultati strukturnih i mehaničkih ispitivanja sučeonih spojeva raznorodnih aluminijumskih legura AlCu4,5Mg (AA2024) i AlMg4,5Mn (AA5083) zavarenih postupkom FSW. Primenom optimizovang alata za zavarivanje, spojene su ploče debljine 6 mm. Međusobni položaj ploča u spoju je variran tako da je u prvom slučaju ploča od AA2024 pozicionirana na strani napredovanja a ploča od AA5083 na povratnoj strani spoja. U drugom slučaju položaj ploča je bio obrnut. Korišćeni su sledeći parametri zavarivanja: brzina rotacije alata nije menjana i iznosila je 750 obr/min a brzina zavarivanja iznosila je 73 i 93 mm/min. Dobijeni su spojevi bez prisustva grešaka i sa glatkom odnosno prihvatljivo ravnom površinom spoja. Analiziran je uticaj parametra zavarivanja na dobijenu strukturu i mehanička svojstva spoja. Oblik grumena i u njemu prisutnih koncentričnih krugova, zavisi od brzine zavarivanja i položaja ploča u spoju. Do loma uvek dolazi na strani spoja gde je pozicionirana ploča od legure AA5083. Karakteristično je da se lom uvek dešava na rastojanju od oko 21 mm od centra spoja. In this work, the structural and mechanical properties of friction stir welded dissimilar butt joints of AA2024-T351 to AA5083-H112 aluminum alloys were evaluated. Plates of 6 mm thick were friction stir welded with optimized tool. In the first case, plate of AA2024 was positioned on the advancing and plate of AA5083 was on the retreating side of the weld. In second case, position of the plate was opposite. Specimens were welded using rotation rate of 750 rpm and welding speed of 73 and 93 mm/min. Specimens were defect free, with good or acceptable weld surface. The effects of rotation and lateral speed of the welding tool were related to structural features and mechanical properties. The structural appearances of concentric rings in the nugget zone were controlled by tool speed and plate position. Structural analysis of the joint cross-section, revealed the distinct lamellar bands. The joints consistently failed on the AA5083 aluminum alloy plate. Failures were observed through the heat-affected zone at distance of approximately 21 mm from weld center.

Zavarivanje trenjem sa mešanjem - ZTM (eng. Friction Stir Welding - FSW) je relativno mlad postupak zavarivanja u čvrstom stanju nastao na Institutu za zavarivanje (TWI) u Londonu, krajem 1991. godine. Prva primena ZTM postupka se vezuje za železnicu i zavarivanje aluminijuma i njegovih legura ali se sa vremenom proširio opseg primene tako da se danas ovim postupkom uspešno zavaruje veliki broj čistih metala, legura, ali i nemetala, u svim industrijskim granama (železnica. avioindustrija, automobilska, brodogradnja itd.). Dve decenije po nastajanju, ZTM postupak se ipak, najviše koristi za zavarivanje aluminijuma i njegovih legura, te nije iznenađujuće što su prvi koraci standardizacije ZTM postupka vezani za zavarivanje aluminijuma. Ovim radom se skreće pažnja na osnovne pojmove kod ZTM koji su dati u postojećim standardima i predlažu odgovarajući pojmovi na srpskom jeziku. Friction Stir Welding is relatively young welding process in solid state which is created in The Welding Institute - London, during 1991 year. The first application is connected with railway and aluminum and aluminum alloys welding but later the application range is extended, so today this process successfully welded many pure metals, alloys also, non-metals in all industrial branches (railway, aircraft, automotive, shipyard etc). Two decades after formation, FSW process is the mostly used for aluminum and aluminum alloys welding, so it is not surprise that the first step in FSW standardization is connected to aluminum welding. The aim of this paper is to draw attention to basic terms for FSW which are presented in actual standards and suggested appropriated terms on Serbian language.

Some experiences in elimination of tunnel type defect Friction Stir Welding of Al alloy 5052-H32 are presented in this paper. In order to evaluate the influence of the processing parameter (ratio between rotation and translation speed during welding) on the occurrence of tunnel type defects and quality of welded joint, different welding parameters were varied. Welded joints were tested by means of both nondestructive (visual inspection, X-ray inspection) and destructive (metallographic, bending, tension and hardness) testing. Best results were obtained for the ratio between 6.45 and 8.22. Results suggest that with this ratio, the material flows around the pin with optimal speed, i.e. sufficient amount of material is available to fulfill the gap and prevent tunnel formation. U radu su predstavljena iskustva na eliminaciji greške tunela u zavarenim spojevima dobijenih zavarivanjem ploča postupkom zavarivanja trenjem alatom na leguri Al 5052-H32. U cilju određivanja uticaja parametara zavarivanja (odnos brzine rotacije alata i brzine zavarivanja-translacije) na pojavu greške tunela i kvalitet zavarenog spoja, parametri su varirani u širokom opsegu. Zavareni spojevi su ispitivani metodama bez razaranja (vizuelno, penetrantima i rentgenski) i sa razaranjem (metalografski, zatezanje, tvrdoća i savijanje). Zavareni spojevi sa najboljim osobinama postignuti su kod spojeva zavarenih korišćenjem odnosa u opsegu od 6.45 do 8.22. Rezultati ukazuju da su to odnosi koji obezbeđuju optimalni način tečenja materijala oko trna alata, tj. da je kontinuirani dotok materijala na povratnu stranu dovoljan da homogeno popunjava prazninu i spreči pojavu kanala.