Mechanism and Properties of Fabricating and Cleaning-up for (Al₂O₃+Al₃Zr)_p/Al Composites with Electromagnetic Stirring

Under the condition of electromagnetic stirring(EMS),the composites of Al2O3、Al3Zr particulates reinforced aluminum matrix was synthesized by Al-Zr(CO3)2 components through the direct melt in-situ reaction method.The microstructure and properties of composites were studied.The mass transfer and diffuseness in solid-liquid phases could be accelerated by EMS and in-situ reactions were improved largely.The fraction volume of particulates in aluminum matrix was enhanced and the particulates were well distributed in the matrix.Casting defects were dramatically decreased,which led to a high cleanness of aluminum matrix.When the added amount of Zr(CO3)2 was 20%,the tensile strength was 202.6MPa,which was increased by 34.8％ compared to that of samples fabricated without electromagnetic stirring.