Papers by Keyword: PMMA Material

Abstract: This article describes a method to measure the refraction index of transparent material by combining the characteristics of transparent material with 2D digital image correlation. The method established the relationship between refraction index and in-plane displacement of speckles using the refraction principle. In-plane displacement can be calculated by the 2D digital image correlation directly. Refractive index of PMMA were obtained by speckle patterns which were recorded by single camera. Results showed that the calculation is very close to the existing PMMA material refractive index value that proved the feasibility and the effectiveness of the method. Of course, this method also can be used to calculate the thickness of the transparent material to widen its using fields.

Abstract: Fracture studies of components involving mode III loading are rare. This paper concentrates on mixed-modes I, II and III fracture testing of brittle PMMA material and summarises an extensive experimental investigation. Karpour and Zarrabi have developed a special pair of grips for which they have received a patent. These grips allow the application of various mixtures of modes, including mode III, using a universal testing machine. To measure the three-dimensional crack-tip opening and sliding displacements, Karpour and Zarrabi have also developed a novel stereo machine vision system whose description is included in the paper. The measured critical crack-opening displacements presented in normalised format with potential of being used to assess the integrity of any component against elastic fracture and they compare well with limited pertinent data available from literature.