Preparation And Application Of Compound Refining Flux For Aluminum Alloy

The content of inclusions and gas in aluminum and aluminum alloys meltdirectly affect the performance of the casting, the melt cleaning focus on the melt ofthe exhaust purification. In order to obtain higher capacity of removing inclusion andgas, the compound renning flux has been successfully synthesized through selectionand optimization of proper fiux compound. By means of direct-reading spectrometer,XRD, hydrogen tester, OLYMPUS-BX51microscope-universal testing machines andother electronic equipment, the microstrueture and mechanical properties of castalloys were studied to evaluate the purification efficiency. The conclusions can bemade as following.l) Through selection and optimization of proper fiux compound，the compoundrenning flux contained （50wt%NaCl+50wt%KCl), Na3AlF6, C2Cl6, and CeF3.2) The range of proportions of each component in refining agent can be madeas following. Based on the basic component of refining agent (50wt%NaCl+50wt%KCl),5%to15%cryolite, and15%to25%range of hexachloroethane, less than10%of the rare earth fluoride (C2Cl6) should be added.3) With orthogonal test finished, among those fluxes containing compounds ofNaCI, KCI, Na3AlF6, C2Cl6,and CeF3, the flux with NaCl/KCl13.2g, Na3AlF63g,C2Cl65g, CeF31g has the best purification performance for aluminum alloys.WhenA356alloys were purified by this flux, they incorporated residual inclusion and voidwith volume fraction of0.15vol.%respectively; hydrogen contents of0.12mL/100gAl.4) Compared to the untreated and normal flux, the flux can respectivelydecrease the content of gas (hydrogen) about3and2times, reduce content of voidand inclusion2and4times，and decrease the level of pinhole about4and2times.The tensile strength were increased respectively by19.5%s and9%, elongation δ alsocan be improved, the mechanical properties of aluminum alloy was improved.