Micromechanical parameters from macromechanical measurements on glass-reinforced polybutyleneterepthalate

Many elegant techniques have been developed for the quantification of composite micromechanical parameters in recent years. Unfortunately most of these techniques have found little enthusiastic support in the industrial product development environment. We have developed an improved method for obtaining the micromechanical parameters, interfacial shear strength, fibre orientation factor, and fibre stress at composite failure using input data from macromechanical tests. In this paper we explore this method through its application to injection moulded glass-fibre-reinforced thermoplastic composites. We have measured the mechanical properties and residual fibre length distributions of glass-fibre-reinforced polybutyleneterepthalate containing different levels of glass fibre. This data was used as input for the model. The trends observed for the resultant micromechanical parameters obtained by this method were in good agreement with values obtained by other methods. Given the wealth of microstructural information obtained from this macroscopic analysis and the low level of resources employed to obtain the data we believe that this method deserves further investigation as a screening tool in composite system development programmes.