Effects of manufacturing parameters on residual stresses in SiC/Ti composites by an elastic–viscoplastic micromechanical model

• Residual stress in SiC/Ti composite is estimated by using a new micromechanical model.
• The presented model provides accurate results when compared with experimental data.
• At cooling rates lower than 1.5 °C/s, residual stresses in the matrix are sharply diminished.
• Transverse strength of the composite decreases by increasing fiber volume fraction.

A three-dimensional micromechanical model is developed to study the effects of manufacturing process and fiber volume fraction (FVF) on the thermal residual stresses (RS) in SiC/Ti–6Al–4V metal matrix composite (MMC). The model includes the effects of coating, interaction layer and stress relaxation. Effects of stress relaxation are considered by incorporating appropriate creep law for the Titanium matrix. In this paper, attention is focused on manufacturing procedure dependent variable which influences global behavior of the MMC. Predictions made by the presented finite element model show acceptable correlation with the reported experimental data. Results reveal that viscoplastic behavior of the matrix has significant effects on the residual stresses at cooling rates lower than 10 °C/s. Results show that high value of FVF and manufacturing temperature leads to high state of RS within the composite. For these cases, it is recommended that the composite cooled down with cooling rates lower than 0.64 °C/s.

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