| Electromagnetic casting(EMC) is a new material processing method, a comprehensivesubject based on magneto-hydrodynamics (MILD) and combined with metallurgicalengineering. The outstanding merits of EMC lie in its high smooth surface, good mechanicalproperties and high production efficiency, which has become an important method to realizetandem rolling in continuous casting and produce high qualified aluminum alloys. However,the various technological parameters and high control precision requrire realizing auto-controlof EMC in industry. Electromagnetic continous casting(EMCC) could clear up lots of defectssuch as segregation, lard in ingot surface.consequently the ingot with better surface qualityand miacrostructure.The effects of Zr on the cast microstructure and mechanical properties ofAl-4.0Cu-1.4Mg-0.5Mn high strength aluminum alloy by electromagnetic continuous castingwere studied by using optical microscope hardness measurement tensile test scanning electronmicroscope and XRD et. The results show that Zr can remarkably improve the properties ofalloys, The strengthening mechanism are considered as fine grain strengthening anddispersion strengthening; The macrohardness of the alloy with Zr increase by 3.91%, thetensile strength and the yield strength of alloy with Zr can raise about 3.90% and 4.82%respectively and extend ratio improve by 48.66% compared with the alloy without Zr inas-cast state. The alloy with Zr express ductile fracture mechanism.In this paper the Al-4.0%Si aluminum alloys were made by EMC. Compared with that ofdirect chill casting(DCC), Results show that the EMC ingots have better and uniform grainmicrostructure and excellent surface. The tensile strength of EMC ingots is 1.31%times ashigh as DCC ones and the extend ratio attain about 2.5 times in as-cast state. The fatigueintension of EMC ingots improve by 2.72; The EMC specimens also express temper fatiguefracture mechanism, then the test sample of DCC ingots show cleavage fracture mechanism.
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