Development of a novel mechanical tester for microfracture analysis


  • Kheng Lim Goh Newcastle University Singapore
  • Ye Seng Chen Newcastle University Singapore
  • Roy Jia Jun Chua Newcastle University Singapore
  • Tze Chow Fong Newcastle University Singapore
  • Yu Ker Woh Newcastle University Singapore
  • Eddie Zhi En Tan Newcastle University Singapore
  • Rachel Wang Newcastle University Singapore



elasticity, fracture, flax fibre, oil palm empty fruit bunch fibre, coir fibre


The study of the mechanical properties of materials is important in the design and fabrication of any microscale product. Acquiring information such as the fracture toughness, fatigue limits, ultimate tensile and yield strength of these materials would help to determine the reliability of the final product made using the material. Traditionally, these material properties are obtained via mechanical testing on a macroscale tester such as the machines produced by Instron. However, mechanical testing of ‘softer’ materials with a microscopic size is more complicated as the test procedures and equipment have to address concerns such as clamping and alignment of specimen. Recent advancement in micromachining and micro-manufacturing has resulted in the availability of advanced and affordable instrumentation that can be applied to precisely manipulate the materials at microscopic dimensions; this provides the impetus to the development of microscale mechanical testers to study the micro-elasticity and micro-fracture mechanics of soft materials. The focus of this report is on the development of a micromechanical tester that can be used to study micrometer thick biomaterials and biological tissues. The tester can be mounted onto an X-Y stage of an inverted or compound microscope to observe the microscopic deformation and microfracture of the test specimen during testing. Three case studies are presented here to illustrate the performance of the mechanical tester. These studies address the characterisation of the mechanical properties of the flax fibre, oil palm empty fruit bunch fibre and coir fibre in dry and wet states.

Author Biography

Kheng Lim Goh, Newcastle University Singapore

Associate Professor of Mechanical Engineering

MInstP, MIMechE, CPhys, CEng



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