The research of interfacial reaction behavior and stress-strain law towards laser cladding of titanium alloys on CFRP

Abstract

In this paper, laser cladding technology is utilized to respectively prepare TC4 alloy and TC4 alloy doped with AlSi10Mg coatings on carbon fiber reinforced thermoplastics (CFRP). The interface between TC4 coating and CFRP substrate with poor performance would pose significant challenge in the engineering application of composite components. Thus, the interface quality is mainly studied and evaluated from two aspects, namely the interfacial reaction behavior and the stress-strain state. On the one hand, thermal analysis (TG-DSC) and phase diagram analysis are utilized for investigating the reaction types and processes at the CFRP/TC4 coating interface. Then, the growth mechanism of TiC crystals under rapid non-equilibrium conditions of laser cladding is revealed. On the other hand, the HRTEM stress-strain field at the CFRP/TC4 coating interface is investigated using geometrical phase analysis (GPA), which finally disclosures the effect of Al element on the stress-strain law at interface and establishes the relationship between the stress and the interface property. Overall, this study provides comprehensive analysis and dissection for interfacial problems between CFRP and TC4, which lays a solid foundation for solving difficulties of the low-quality connection and easy-failure interface between heterogeneous materials (CFRP and TC4). This will allow these two materials to form better aerospace composites that can withstand greater loads and serve in harsher space environment.

Keywords

• Laser cladding
• CFRP/TC4 coating interface
• Interfacial reaction behavior
• Stress-strain law