Metallography and Microstructures of Copper and Its Alloys

Abstract

This article describes the microstructure of copper alloys, including copper-zinc (brasses), bronzes, copper-nickel, and copper-nickel-zinc, and examines the effect of oxygen content on alloy phases observed in different product forms. The article also discusses inclusions, etchants, and the effect of composition and processing on grain structure and growth rates.

Authenticity of Benin metalworks evaluated by inductively coupled plasma mass spectrometry and lead isotope analyses

“…The single-phase microstructure of the matrix was composed of a cored α-Cu solid solution, resulting from a zinc content lower than the solubility limit in copper (about 35% Zn at room temperature) (Tables 1 and 2). In all cases, non-metallic inclusions and lead globular precipitates (insoluble in copper [52]) were also visible in interdendritic spaces. The EDS maps evidenced iron phosphide inclusions (Fig.…”

“…Concerning the plaques, the presence of recrystallized non-homogeneous twinned grains in areas corresponding to surface decoration (Fig. 2c) was probably due to multiple cycles of hammering and annealing (usually between 500 °C to 800 °C for copper-based alloys), performed in order to emphasize the details of adornments and restore metal workability and toughness [52]. The single-phase microstructure of the matrix was composed of a cored α-Cu solid solution, resulting from a zinc content lower than the solubility limit in copper (about 35% Zn at room temperature) (Tables 1 and 2).…”

Metal Fragments of Roman Pipes from Pompeii: Investigations on Copper-Based Alloys, Corrosion Products, and Surface Treatments

“…Chemical etching with FeCl 3 /HCl showed a recrystallized structure throughout the entire sample thickness, with the presence of several slip bands. This microstructure indicates a final cold working step after hot working (Figure 4) [11].…”

Laser-cleaning effects induced on different types of bronze archaeological corrosion products: chemical-physical surface characterisation

“…For the bulk analyses, an etching aqueous ferric chloride solution (5 g FeCl3, 15 ml HCl (40% conc. ), 60 ml H2O) suitable for archaeometallurgical Cu-based alloys was used to produce grain contrast [32][33][34]. The procedure was carried out at room temperature.…”