Evaluation of Friction at High Strain Rate using the Split Hopkinson Bar

Abstract:

The present work aims at studying the influence of strain rate on the frictional behaviour of AA7075 aluminium alloy in the O-annealed temper state. To this purpose, ring compression tests were performed both under quasi-static and dynamic loading conditions. The high strain rate tests were carried out by means of the Split Hopkinson Tension-Compression Bar in the direct version. In both cases, hollow cylindrical samples, characterised by an initial outer diameter to inner diameter to height ratio of 6:3:2, were tested under dry condition and by lubricating with molybdenum disulphide grease. The different frictional behaviour exhibited by AA7075-O under quasi-static and dynamic loading conditions can be attributed to the strain rate effect both on the plastic flow behaviour of the deformed material, and on the thickness of the lubricant film.

• Periodical: Key Engineering Materials (Volumes 651-653)
• Pages: 108-113
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.651-653.108
• Online since: July 2015
• Authors: Archimede Forcellese, Edoardo Mancini, Marco Sasso, Michela Simoncini*
• Keywords: Aluminium Alloy, FEM, Frictional Behaviour, High Strain Rate, Ring Compression Test, Split Hopkinson Bar

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DOI: 10.4028/www.scientific.net/kem.651-653.114