Effect of TiC nanoparticles on microstructure and corrosion resistance of laser cladding Al-CNTs composite coatings on AZ31 alloy

ABSTRACT

Al-CNTs composite coatings were successfully prepared on AZ31 alloy using laser cladding (LC). The effect of TiC nanoparticles on microstructure and corrosion resistance of the LC Al-CNTs and Al-TiC-CNTs composite coatings were investigated. The LC composite coatings were composed of α-Mg solid solution phase and β-Al₁₂Mg₁₇, Mg₂Al₃, Mg₃₂(Al,Zn)₄₉ and TiC compound phases. A sound metallurgical bonding interface was produced between the LC composite coatings and AZ31 alloy. The surface microhardness and corrosion resistance of the LC composite coatings, which were gradually decreased with increasing the content of carbon nanotubes (CNTs) and TiC nanoparticles, were significantly enhanced compared to those of the AZ31 alloy. The LC Al-CNTs (99 wt% Al + 1 wt% CNTs) composite coating exhibits excellent surface microhardness and corrosion resistance. The mean surface microhardness, self-corrosion potential and self-corrosion current were 266.4 HV, −1.233 V and 2.55 × 10⁻⁵ A, which were 426.2%, 78.9% and 16.5% of the AZ31 alloy, respectively.

KEYWORDS:

• Laser cladding
• microstructure
• corrosion resistance
• Al-CNTs
• Al-TiC-CNTs

Acknowledgments

The authors would like to thank the National Natural Science Foundation of China (No. 52064048), the Innovation Team of Education Department of Shaanxi Provincial Government (No. 22JP105), Science and Technology Bureau of Yulin (No. CXY-2022-083, CXY-2020-006-01) and High-Level Talent Project of Yulin University (No. 2023GK10) for funding the project.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The work was supported by the Education Department of Shaanxi Provincial Government [22JP105]; Yulin University [2023GK10]; National Natural Science Foundation of China [52064048]; Science and Technology Bureau of Yulin [CXY-2022-083, CXY-2020-006-01].