Investigation on Manufacturing Process in Some Elamite Copper Alloy Artefacts from Haft Tappeh, South-west Iran
The archaeometallurgy of copper have been pioneer technologies in ancient Iran and goes back to about ten thousand years ago in Iranian Plateau [1, 2]. The Haft Tappeh Middle Elamite Site is located in Southwest Iran and have been an important city belonging to early phase of Middle Elamite period (14th century BCE) [3, 4]. Based on various metallurgical evidences found in archaeological excavations, such as metalworking workshop, slag, smelted copper as well as numerous copper alloy artefacts, extensive metallurgical activities have done in Haft Tappeh and it has been an important center in smelting and manufacturing copper alloys in second millennium BC [4, 5]. To identify metallurgical process of metallic artefacts in Haft Tappeh including alloying composition, inclusions and phases as well as manufacturing and shaping, seven metallic fragments have studied by Scanning Electron Microscopy with Energy Dispersive X-ray Spectrometry (SEM-EDS) and optical microscopy.
Metallography and microstructure of ancient and historic metals
This book provides an introduction to the structure and morphology of ancient and historic metallic materials. It deals extensively with many practical matters relating to the mounting, preparation, etching, polishing, and microscopy of metallic samples and includes an account of the way in which phase diagrams can be used to assist structural interpretation. The text is supplemented by an extensive number of microstructural studies carried out in the laboratory on ancient and historic metals.
Evolution of carbide precipitates in Hastelloy N joints during welding and post weld heat treatment
Abstract The effects of welding and post weld heat treatment (PWHT) on the morphology, composition and lattice parameter of the precipitates in the welding joints of Hastelloy N alloy have been investigated. Joint samples were prepared using a gas tungsten arc welding process with ERNiMo-2 fillers, and then solid-solution treated at 1100 °C for 20 min. After welding, eutectic M6C carbides can be observed in the heat affected zones (HAZ) and weld zones (WZ). These eutectic M6C carbides become spheroidized during the following PWHT. The concentration of Si decreases during the transformation from the primary ones to eutectic ones, and then increases during the spheroidizing process. The total concentration of Si + Cr in M6C carbides remains stable during welding and PWHT. At the same time, the heat leads to the outward diffusion of Mo from the M6C carbides, which results in a decrease of the lattice parameter.