Strength of synthetic diamonds under tensile stresses produced by picosecond laser action
S. A. Abrosimov1, A. P. Bazhulin1, A. P. Bolshakov1,2, V. I. Konov1,2, I. K. Krasiuk1, P. P. Pashinin1, V. G. Ralchenko1,2, A. Yu. Semenov1, D. N. Sovyk1,2, I. A. Stuchebryukhov1, V. E. Fortov3, K. V. Khishchenko3, A. A. Khomich1,2
1Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow, 119991 Russia
2MEPhI National Nuclear Research University, Moscow, 115409 Russia
3Joint Institute for High Temperatures, Russian Academy of Sciences, Moscow, 125412 Russia
Keywords: synthetic diamonds, laser pulse action, negative pressure, spall strength, phase transformations
Abstract
Results of an experimental-theoretical study of spallation in synthetic diamonds are presented. In this study, data were first obtained on dynamic tensile strength of poly– and single-crystal diamond samples at mechanical loads of up to 0.34 TPa and strain rates of 10–100 μs–1. Shock-wave loading was performed by 70 ps laser pulses on a Kamerton–T facility using a Nd:glass laser (second harmonics λ = 527 nm, pulse energy of up to ≈3 J) at intensities of ≈8 TW/cm2. The obtained maximal value of the spall strength ≈16.4 GPa is 24% of the theoretical ultimate strength of diamond. Raman scattering experiments showed that a small amount of diamond was graphitized in the spall area on the backside of the sample.
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