MICROHARDNESS STUDIES AND SURFACE ANALYSIS OF 4-HYDROXY N-METHYL 4-STILBAZOLIUM BESYLATE SINGLE CRYSTAL

Abstract

The Vickers and Knoop Microhardness studies were carried out on 4 - hydroxy N–methyl 4- stilbazolium besylate single crystal, subjected to loads 10, 25 and 50 g. The measurements were made at room temperature with the indentation time as 10 s. The Vickers hardness number and the Knoop Microhardness number were found to increase with the applied load due to reverse indentation size effect. The Meyer’s index number, fracture toughness, brittle index and yield strength were calculated from Vickers hardness value. The Young’s modulus was calculated using the Knoop hardness value. Hardness anisotropy has been observed in accordance with the orientation of the crystal. Laser damage threshold studies have been carried out for the crystal using a Q-switched Nd:YAG laser of 10 ns pulses. The surface of the grown crystal was analysed with etching. The results are discussed in detail.