Troisiéme Conférence Européenne sur les Matériaux et les Procédés Avancés
J. Phys. IV France 03 (1993) C7-1485-C7-1489
Investigation of the mechanical properties of silica glasses by indentation testsA. JUHÁSZ1, G. VÖRÖS1, P. TASNÁDI1, I. KOVÁCS1, I. SOMOGYI2 and J. SZÖLLÖSI2
1 Institut for General Physics, Lóránd Eötvös University, 1088 Budapest, Muzeum krt. 6-8, Hungary
2 Bródy Research Center, G.E. Tungsram, Budapest, Hungary
Soda lime silica glasses were investigated by continuous indentation tests. The load indentation depth curves were taken during the loading as well as the unloading period by a computer controlled MTS machine. It was found that the loading force is a quadratic function of the indentation depth during both the loading and unloading stage of the deformation. The validity of the quadratic relationship in the case of the unloading stage seems to be characteristic only for glasses. Taking into account the elastic relaxation of the indentation depth an estimation is given for the size of the hydrostatic core which is necessary to symmetrize the stress field around the indenter. Using the measured length of the radial cracks started from the corners of the Vickers indentation pattern the KIC values were calculated.
© EDP Sciences 1993