A study of monetite precipitation on HT-C/C composites by induction heating method at different substrate temperatures

Induction heating deposition (IHD) of monetite coatings on H2O2-treated carbon/carbon composites (HT-C/C) for various loading time at different substrate temperatures ranging from 343 K to 373 K was investigated in this study. The phase, morphology and composition of these coatings were characterized by SEM, XRD, EDS, and their adhesion to the HT-C/C substrates was evaluated by a scratch test. The results showed that no obvious changes were found in morphology, composition and phase of monetite coatings prepared by IHD at different substrate temperatures, while their denseness increased with elevating substrate temperature. In addition, the contents of monetite deposits on HT-C/C increased linearly with increasing loading time, which showed that the IHD of monetite coatings on HT-C/C was controlled by a surface chemical reaction. The deposition activation energy of them was 68.7 kJ/mol. According to these results, suggestions for improving adhesion of monetite coatings to HT-C/C were provided.

► The effect of substrate temperature on the adhesive of monetite coatings to HT-C/C was disclosed.
► The monetite coating on HT-C/C could reach a critical load of 18 N or so.
► The deposition activation energy of these monetite coatings was 68.7 kJ/mol.