Experimental results and strength model identification of pure iridium. (August 2017)

• Record Type: Journal Article
• Authors: Scapin, Martina; Peroni, Lorenzo; Torregrosa, Claudio; Perillo-Marcone, Antonio; Calviani, Marco; Pereira, Laura Gomez; Léaux, Floriane; Meyer, Mickaël
• Is Part Of: International journal of impact engineering. Volume 106(2017)
• Page Start: 191
• Page End: 201
• Publication Date: 2017-08
• Subjects: Refractory metal -- High temperature -- High strain-rate -- Johnson-cook -- Recrystallization temperature -- Fracture analysis; Impact -- Periodicals; Shock (Mechanics) -- Periodicals; Impact -- Périodiques; Choc (Mécanique) -- Périodiques; Impact; Shock (Mechanics); Periodicals; 620.1125
• DOI: 10.1016/j.ijimpeng.2017.03.019
• Languages: English
• ISSNs: 0734-743X

Abstract

Highlights: Mechanical characterization of pure iridium. Tension tests at different temperatures and strain-rates. Fracture surface analysis. Johnson-Cook model identification. Recrystallization temperature. Abstract: Intense and high energy proton beams are impacted with fixed materials (targets) in order to produce new particles and secondary beams at CERN. In some of these targets, the requirement of reaching high yield production of secondary particles points out to the use of high density materials. The interaction of the beam with the atoms and nuclei of these materials produce extremely fast depositions of energy, highly soliciting them from thermo-structural point of view due to subsequent rise of temperature and pressure waves. Iridium is a good candidate material since exhibits very high density, high melting point, good strength and stability at high temperature, and resistance to thermal shock. The main goal of this study is the investigation of the mechanical behaviour at different temperatures and strain-rates in tensile loading condition of pure iridium. A series of tests at room temperature at different strain-rates (from 10 −3 s −1 up to 10 4 s −1 ) was performed in order to obtain information about strain and strain-rate sensitivity of the material. In addition, a series of tests at different temperatures in both quasi-static and high strain-rate loading conditions was performed in order to obtain information about the thermal softening of the material (from room temperature up to 1250 °C). The experimental data were used to identify a strength model able to predict the material behaviour over wide ranges of variation of the variables of interest.