The Selection of Filler Metal and Flux for 2A50 Al Alloy Brazing

The filler metals and fluxes suitabled for 2A50 aluminum alloy brazing were selected according to the feature of 2A50 aluminum alloy and the test of spreadability and clearance fillabitity.Shear tests after the selection indicate that mesothermal CsF-AlF3 flux with high activity and good ability of removing oxide film is appropriate for brazing heat treatment strengthened aluminum alloys containing magnesium element.Adopting CsF-AlF3 flux matched with Al-Cu-Ag-Zn and Zn-Al-Be filler metals respectively obtain good results for brazing 2A50 aluminum alloy.Matching Zn-Al-Be filler metal with CsF-AlF3 flux for brazing 2A50 aluminum alloy could make the shearing strength reach to 143.2 MPa when the lap gap and the lap length are 0.2 mm and 2.3 mm separately.