Production of Copper Ingots from Industrial Waste: An Innovative Solid-State Sintering Process with Microstructural and Crystallographic Analysis

This study investigates the recycling of industrial waste copper chips generated during the processing of copper chips containing approximately 5% magnesium. An innovative patented modification was integrated with the classical solid-state sintering method to directly produce copper ingots from these wastes. Unlike conventional powder metallurgy techniques, the process employs a low-pressure (7 bar) and short-term (5 minute) sintering step without prior surface cleaning. Initially, the chips undergo pre-compression at 200 degrees C, followed by heat treatment at 1035 degrees C, and subsequently a secondary pressing to yield copper ingots. X-ray diffraction analysis predominantly identified the face-centered cubic copper phase, while energy dispersive spectroscopy indicated only trace amounts of oxygen and iron. The abbreviated sintering duration successfully preserved over 97% of the metallic copper phase and minimized oxide formation. Scanning electron microscopy confirmed a homogeneous microstructure, with crystallite sizes and morphology optimized based on the sintering conditions. This approach offers substantial advantages in terms of energy savings, production efficiency, and environmental sustainability.

Journal

RUSSIAN JOURNAL OF NON-FERROUS METALS

Year

2025

Volume

66

Issue

4

Pages

210-222

ISSN

1067-8212

eISSN

1934-970X

DOI

10.1134/S1067821225600632

WoS UID

WOS:001598594900005