Temperature and weldline effects on tensile properties of injection moulded short glass fibre PC/ABS polymer composite

The effect of weldline and temperature on tensile properties of injection moulded PC/ABS blend reinforced with different concentration levels of short glass fibres was investigated between 23 and 100 °C. The weldline was formed in the moulded specimens by direct impingement of two opposing melt fronts. It was found that weldline had no significant effect on tensile modulus with weldline integrity factor in the range of 1–0.98. Tensile modulus for both weld and unweld specimens increased linearly with increasing volume fraction of fibres, ϕf, and decreased linearly with increasing temperature. Tensile strength of both weld and unweld tensile specimens increased non-linearly with increasing ϕf reaching a maximum at ϕf≈ 0.16 for specimens without weldline and ϕf≈ 0.12 for specimens with weldline. A linear dependence with respect to ϕf was found for both weld and unweld tensile strengths for fibre volume fractions in the range 0–0.1. It was found that below the glass transition temperature of the matrix, tensile strength of the composite with and without weldlines decreased linearly with increasing temperature. The weldline integrity factor for tensile strength decreased with increasing ϕf, but showed no significant variation with respect to temperature.