Mechanical Characteristics of As2S3 Glasses Induced by Doping with Bismuth.

This paper presents and discusses the results of the instrumented indentation test of the samples of the system Bix(As₂S₃)_100-x, x = 1:5, 3, 5, and 7 at.%. Measurements of mechanical parameters were performed using a Fischerscope HM2000 S nanoindentation device. The experimental data obtained by measuring the microhardness parameters were used to determine some other mechanical quantities that are important for the characterization of the examined materials in terms of their potential applications. For the first three compositions, the results indicated an increase in the microhardness with the increase in the content of doping atoms, which can be interpreted as an enhancement of the strength and stiffness of the structural network. The lower value of microhardness of the sample with the maximum content of Bi can BE associated with the specific structure of this composition. The pronounced indentation size effect was also detected on the indentation curve in the range of smaller loads. According to the model of elastic-plastic deformation, applied for the description of indentation size effect measured for the investigated chalcogenides, the largest value of the elastic recovery was observed for the sample Bi₇(As₂S₃)₉₃. The calculated values of the elasticity modulus show that the glass with x = 5 at.% Bi is characterized with the highest atomic packing density. [ABSTRACT FROM AUTHOR]