Recycling of Ck45 Steel Chips by Spark Plasma Sintering: Comparison with Conventional Machining and Environmental Assessment

Sayyed Mohammadreza Sedehi ¹ ( Ph.D. Student, School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran, Iran )
Zahra Maleki ² ( Department of Engineering, Gonabad University, Gonabad, Iran )
Fatemeh Norouzi Palangani ³ ( Department of Materials and Metallurgical Engineering, Amirkabir University of Technology, Tehran, Iran )
Ahmadreza Rastegar ⁴ ( Faculty of Economics and Administrative Sciences, Ferdowsi University, Mashhad, Iran )
Mohammad Khakpour ⁵ ( Fadak Machinery Complex, Gonabad, Iran )

Submited date : 2025-05-17 Accepted date : 2025-10-13

Keywords: Steel, Recycling, Machining, Chips, Spark Plasma Sintering (SPS),

Abstract :

Sustainable approaches to material recycling are crucial for reducing the environmental footprint of manufacturing processes. In this study, machining chips are utilized as a valuable resource for recycling, thereby enabling both waste reduction and the development of more cost-effective and environmentally sustainable production processes. Through this method, powder production for advanced manufacturing techniques such as Spark Plasma Sintering (SPS) is proposed as an efficient and environmentally sustainable alternative to conventional machining methods. In this research, a closed-loop recycling process was established using CK45 steel, where machining chips were successfully converted into powder feedstock and consolidated into bulk specimens. These specimens were subjected to hardness testing and X-ray diffraction (XRD) analysis. The results demonstrate that this method not only enhances mechanical properties, including an increase of approximately 30 hardness units, but also provides measurable environmental advantages compared to traditional machining. The application of Spark Plasma Sintering facilitates the fabrication of components with advanced performance characteristics while reducing material waste and associated environmental risks. These findings provide a new perspective for critical industries, such as aerospace and automotive, where environmental impact reduction and efficiency enhancement are achieved in parallel with the advancement of sustainable technologies.

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