Effect of Rare Earth Element on Microstructure and Properties of <i>in situ</i> Synthesized TiB₂/Al Composites

• Main Authors: QU Min, LIU Xin, CUI Yan, LIU Feng-bin, JIAO Zhi-wei, LIU Yuan
• Format: Article
• Language: zho
• Published: Journal of Materials Engineering 2018-03-01
• Series: Journal of Materials Engineering
• Subjects: rare earth element; TiB₂/Al composites; microstructure; tensile property; wettability
• Online Access: http://jme.biam.ac.cn/CN/Y2018/V46/I3/98

The effect of rare earth element Ce, Sc and Er on TiB₂ particles and matrix alloy micros-tructure of TiB₂/Al composites was studied with <i>in situ</i> synthesis method. It shows that the addition of rare earth element improves the microstructure and properties of TiB₂/Al composites notably. The particles of TiB₂ are relatively homogenously distributed as adding 0.3% (mass fraction) rare earth element Sc and Er, moreover, it is Er that refines the microstructure of matrix alloy most significantly, then is Sc. Similarly, it is demonstrated that the addition of Sc and Er results in better tensile strength, which is enhanced by 32% and 31%, respectively; the addition of Er also leads to the best ductility by 85% with optimal tensile property. Meanwhile, fracture morphology analysis reveals that the fracture of the composites is microporous gathered ductile fracture when adding Sc and Er. Finally, it is verified that the mechanism of rare earth element on composites lies in two aspects:one is that the addition of rare earth element improves the wettability of the composites and suppresses the agglomeration of TiB₂ particles; the other is that the addition of rare earth element refines the microstructure of matrix alloy and then improves the tensile strength of the composites.