Processing and Microstructures of δ-Al2O3/ AE44 Composite Synthesized by SS-HPDC
A cylinder block with δ-Al2O3/AE44 (Mg–4.0Al–4.1RE–0.3Mn) magnesium matrix composite was manufactured by Slow Shot High Pressure Die Casting (SS-HPDC) technique.The temperature and wall thickness of the fiber added affect its formation.The block is not infiltrated well when the temperature of the preform is below 450oC.Micro-cracks occur if the thickness of the preform is larger than 8.625mm.Microstructures in the AE44 alloy with and without δ-Al2O3 fibers (Saffil) were both investigated by means of X-ray diffraction (XRD),optical microscopy (OM) techniques and scanning electron microscopy combined with energy dispersive spectrometry (SEM-EDS) equipment.The results show that many Al-RE intermetallic compounds present not only in the matrix but also in the composite,although the grain sizes,the concrete types and their distribution differ.Al-RE second phases in AE44 appear around the grain boundaries in large quantities mainly in globular,lamellar and acicular shape but few in particulate shape,while most of them grow on the fibers in small whiskers and only few scatter in the matrix.Meanwhile,the appearance of Mg2Si in the composite may account for the interfacial reaction between the binder in the preform and the matrix alloy.
Slow Shot High Pressure Die Casting Al-RE intermetallic compound AE44 Metalmatrix composite Cylinder block
Li Li Xiaoqin Zeng
School of Materials Science and Engineering, The State Key Laboratory of Metal MatrixComposites,Shanghai Jiaotong University , 800 Dongchuan RD. Minhang District, Shanghai 200240, China
国际会议
the Chinese Materials Congress 2012(2012年中国材料大会(CMC2012))
太原
英文
198-203
2012-07-13（万方平台首次上网日期，不代表论文的发表时间）