Dynamic mechanical properties in a Zr46.8Ti13.8Cu12.5Ni10Be27.5 bulk metallic glass

Dynamic Mechanical Properties in a Zr<SUB>50</SUB>Cu<SUB>40</SUB>Al<SUB>10</SUB> Bulk Metallic Glass

“…As in other bulk metallic glasses, 10) a very large influence is observed: the lower the frequency, the lower the storage modulus G 0 . Furthermore a shift of the maximum of G 00 is also observed towards higher frequencies when the temperature is increased.…”

“…A good agreement is observed, as in other bulk metallic glasses. 8,10) Consequently, this model seems to allow a good description of the elastic and viscoelastic behaviour of amorphous alloys.…”

“…Zr-based metallic glasses are regarded as a new family of attractive materials combining high mechanical properties at room temperature and good forming features at not too high temperature, typically between 300 and 400 C. [1][2][3][4][5][6][7][8][9][10][11] However, since bulk metallic glasses are in an out of equilibrium state, they are not stable, especially in the supercooled liquid region, above the glass transition temperature. In this temperature range the atomic mobility is high enough to allow a significant diffusion and therefore a way to the formation of crystalline particles.…”

“…A simple and direct method is the determination of dynamic mechanical properties: a periodic stress is applied ant the induced periodic deformation " is recorded. 10,[12][13][14] Two quantities are defined: the complex dynamic modulus G ¼ G 0 þ i Á G 00 ¼ =" and the loss factor: tan ¼ G 00 =G 0 . G 0 is the storage modulus and G 00 is the loss modulus (related to viscoelasticity).…”

“…[15][16][17][18][19][20] Therefore another goal of the present paper is to analyze the results of such models. Let us mention that in a previous publication 10) mechanical spectroscopy has been used to investigate the influence of both temperature and driving frequency on the elastic and viscoelastic properties of an other bulk metallic glass (Vit4), but only the amorphous state was considered and the effect of a structural relaxation or of the formation of a crystalline phase was not addressed.…”