Zeng Xiaomei, Singapore

Xiaomei studied BEng (Materials Science & Engineering) and graduated as first class honour from the School of Materials Science and Engineering at Nanyang Technological University in Singapore in 2011.

Xiaomei is presently doing her part-time PhD and working as a research assistant at Nanyang Technological University. The focus of her current research interests includes the study of small volume ceramics fabrication and the exploration of the mechanical properties relevant to the ceramic phase transformation.

 

Superelasticity in small volume zirconia ceramics

Superelastic materials are smart materials that can be deformed to large strains recoverably upon the application of stress. This unique property is originated from the reversible martensitic phase transformation, a displasive and fast transition between the parent and martensite phase. The brittle zirconia ceramics exhibit a martensitic transformation but suffer from cracking at small strains within a few strain cycles, caused by stress accumulation at the high concentrated grain boundaries.

However, by producing martensitic zirconia in small volume, the failure can be suppressed due to higher surface-to-volume ratio and less grain boundaries. Such small volume single crystal/oligocrystal ceramics can be triggered by large stress and are capable of many superelastic cycles without fracture. The superelastic ceramics with this property represent a new class of smart materials with a combination of many advantages such as high energy damping, high mechanical strength and chemical inertness.