In a groundbreaking development for the energy sector, researchers have introduced a novel approach to repairing and remanufacturing components using microwave heating technology. The study, led by Zhengchun Qian from the School of Mechanical Engineering at Nanjing Institute of Technology and Anhui Key Laboratory of Low Carbon Recycling Technology and Equipment for Mechanical and Electrical Products at Hefei University of Technology, presents a promising solution for enhancing the wear resistance of nickel-based superalloys, crucial materials in high-temperature and high-stress environments.
The research, published in the journal *Materials & Design* (which translates to *Materials & Design* in English), focuses on the Inconel 718 alloy, a material widely used in the energy sector due to its exceptional strength and corrosion resistance. The team developed a microwave heating remanufacturing (MHR) technology that successfully repaired grooves in the alloy’s substrate, creating a coating with remarkable properties.
“The MHR coating shows a low porosity of only 2.8% and exhibits a unique gradient microstructure,” explains Qian. “The upper layer is dominated by dendrites, while the middle layer forms cellular crystals with a network-like carbide precipitation, and the lower layer produces a chain-like Laves phase.”
This gradient microstructure contributes to the coating’s impressive microhardness, which gradually decreases from 232 HV at the top to 210 HV at the bottom. The friction and wear experiments revealed that the MHR coating significantly outperforms the substrate, with an average friction coefficient of 0.62, a mass loss of 7.1 mg, and a wear rate of 27.61 × 10⁻⁶ mm³/(N·m). This translates to a more than 50% improvement in wear resistance.
“The dendrites on the top of the MHR coating can withstand large normal loads and transverse shear forces,” Qian notes. “Additionally, the fish-scale layered structure formed after dendrites bending can store wear debris, greatly enhancing the coating’s wear resistance.”
The commercial implications of this research are substantial, particularly for the energy sector. The ability to repair and remanufacture components using MHR technology could lead to significant cost savings and reduced downtime for power plants and other industrial facilities. Moreover, the enhanced wear resistance of the Inconel 718 alloy could extend the lifespan of critical components, improving overall efficiency and reliability.
As the energy sector continues to demand materials that can withstand extreme conditions, the development of MHR technology offers a new avenue for innovation. This research not only provides a novel method for repairing components but also opens up possibilities for designing materials with tailored properties for specific applications.
In the words of Qian, “The proposed MHR technology offers a completely new approach for the repair of parts and components, which could revolutionize the way we maintain and extend the life of critical infrastructure in the energy sector.”