Structure d’outils miniers du XV^e et du XVIII^e siècle interprétation thermomécanique

Thermomecanical and structural study of mining tools from the 18th and the 18th centuries

Université de Technologie de Compiègne, Laboratoire des Matériaux, U.A. 849 CNRS, Membre de l’U.R.A. 34 du CNRS.

Abstract

In the present paper the microstructure of 15th and 18th century mining tools is widely investigated in detail. Archeological research which is basically an interdisciplinary approach was conducted to extract informations contained in these tools. Analytical and microstructural study : alloy composition, mechanical, chemical and heat treatments have led to an improved knowledge of the smith’s ability. Reconstitution experiments were also conducted. A typology of the structures of these ancient mining tools is proposed : they are made by a peen forged steel welded on a ferritic matrix. Bad welding and excessively large grain size promote brittleness ; quenching is always employed, cementation treatment is used once. Mechanical twinning in the ferritic matrix was also observed corresponding to very high strain rate during reconstitution experiments.