镁基复合材料的强韧化研究进展

Progress in Strengthening and Toughening of Magne或um Matrix Composites

镁基复合材料具有密度低、比强度和比模量高、热稳定性好等优点,在航空、航天以及汽车工业领域具有广泛的应用前景。然而,镁基复合材料在强度提高的同时往往伴随着塑性的降低,而且其室温断裂伸长率通常低于5%,这严重制约了该材料的工业推广与应用。而现有的镁基复合材料制备技术及强塑性理论不完善是目前导致其强塑性难以同时提高的主要原因。因此,发展高强韧镁基复合材料制备技术、完善镁基复合材料强塑性机理、突破镁基复合材料的性能瓶颈成为其发展方向。基于此,本文总结了目前镁基复合材料常用的基体与增强体、主要的制备技术、力学性能的研究现状以及相应的强韧化机理,提出了镁基复合材料强塑性调控的方法,并展望了未来发展趋势。

Magnesium matrix composites show great application potential in the aerospace and automobile industries due to a series of advantages,such as low density,high specific strength and modulus,and good thermal stability.However,for traditional magnesium matrix composites,the increase in strength is always at the expense of ductility,and the room temperature elongation to fracture of as-cast magnesium matrix composites is less than 5%in most cases,which severely hinders the development and application of magnesium matrix composites in industries.The main reasons that the strength and plasticity of magnesium matrix composites cannot be improved simultaneously are the imperfections of the current fabrication techniques and strengthening and toughening mechanisms.Therefore,innovating febrication techniques,modifying strengthening and toughening mechanisms and breaking through the performance bottleneck eventually become the development direction of magnesium matrix composites with high strength and ductility.Based on this,this work is aimed at reviewing the commonly used matrix and reinforcements,the main fabrication techniques,the mechanical properties and the corresponding strengthening and toughening mechanisms of magnesium matrix composites.The development tendency of magnesium matrix composites in the future is prospected,and the mechanisms tailoring the strength-ductility behavior of magnesium matrix composites are proposed.