Thermite welding is an exceptional process that does not require additional energy supplies, resulting in welded joints that exhibit mechanical properties and conductivity equivalent to those of the parent materials. The global adoption of thermite welding is growing across various industries. However, in Korea, limited research is being conducted on the core technology of thermite welding. Currently, domestic production of thermite powder in Korea involves recycling copper oxide (CuO). Unfortunately, controlling the particle size of waste CuO poses challenges, leading to the unwanted formation of pores and cracks during thermite welding. In this study, we investigate the influence of powder particle size on thermite welding in the production of Cu-thermite powder using waste CuO. We conduct the ball milling process for 0.5–24 h using recycled CuO. The evolution of the powder shape and size is analyzed using particle size analysis and scanning electron microscopy (SEM). Furthermore, we examine the thermal reaction characteristics through differential scanning calorimetry. Additionally, the microstructures of the welded samples are observed using optical microscopy and SEM to evaluate the impact of powder particle size on weldability. Lastly, hardness measurements are performed to assess the strengths of the welded materials.

1. Introduction
2. Experimental
3. Results and Discussion
    3.1 입도 제어 폐 산화동 분말 분석
    3.2 테르밋 용접 후 미세조직 및 기계적 물성 분석
4. Conclusion
Acknowledgement

• 이한성(아주대학교 에너지시스템학과) | Hansung Lee (Department of Energy Systems Research, Ajou University, Suwon 16499, Republic of Korea)
• 김민수(아주대학교 에너지시스템학과) | Minsu Kim (Department of Energy Systems Research, Ajou University, Suwon 16499, Republic of Korea)
• 안병민(아주대학교 에너지시스템학과, 아주대학교 첨단신소재공학과) | Byungmin Ahn (Department of Energy Systems Research, Ajou University, Suwon 16499, Republic of Korea, Department of Materials Science and Engineering, Ajou University, Suwon 16499, Republic of Korea) Corresponding Author