Characterization, surface preparation, conservation, and corrosion protection of bronze arrow heads from Cairo military museum using nanocomposite coating

Abstract

AbstractThe study focused on examining approximately 32 arrowheads from Cairo’s Qala Salah al-Din military museum, which showed significant signs of deterioration. The main objectives were to investigate the bronze alloy composition of these arrowheads and analyze the physical and chemical characteristics of their patinas. Understanding the causes and mechanisms of corrosion was crucial for developing effective conservation strategies to halt further degradation and identifying the corrosion products and metals involved. To achieve these goals, extensive examinations and analyses were conducted, including metallographic microscopy, SEM–EDS, and X-ray diffraction analysis to scrutinize the chemical composition, metallurgical features, and corrosion products of the bronze samples. Additionally, experimental studies were carried out to determine the most suitable protective coating for preventing future corrosion. Various combinations of ZnO nanoparticles with Paraloid® 48 or Paraloid® 66 coatings were tested on simulated arrowheads, and electrochemical techniques such as EIS and RP were employed for measurement. The results indicated that combining ZnO nanoparticles with either Paraloid® 48 or Paraloid® 66 coatings resulted in lower corrosion rates compared to using each coating alone. Based on these findings, chemical cleaning with ZnO nanoparticles and Paraloid® 48 was selected for treatment to protect the arrowheads' surfaces. Overall, this study provides valuable insights into preservation techniques for these historically significant artifacts.