Microhardness and its related physical constants in solution-grown ammonium sulphate single crystals

被引：33

作者：

Karan, S ^{[1
]}

Sen Gupta, S ^{[1
]}

Sen Gupta, SP ^{[1
]}

机构：

[1] Indian Assoc Cultivat Sci, Dept Mat Sci, Kolkata 700032, W Bengal, India

来源：

MATERIALS CHEMISTRY AND PHYSICS | 2001年 / 69卷 / 1-3期

关键词：

microhardness; work-hardening index; toughness; brittleness; elastic constant; ammonium sulphate;

D O I：

10.1016/S0254-0584(00)00362-X

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

The variation of hardness on (1 0 0) faces of orthorhombic ammonium sulphate crystals, AS [(NH4)(2)SO4], With load were studied. Vickers hardness numbers, H-v, were found to increase with the increase in load. Work-hardening index 'n' was found to be greater than 2 showing soft-material characteristics. Kick's law has been satisfied after making a correction in the observed diagonal length of the indentation impression. The fracture toughness values 'K-c', determined from measurements of crack lengths, were estimated to be 0.078 and 0.073 MN m(-3/2) for (1 0 0) faces at 90 and 100 g, respectively. The brittleness indices 'B-i' were estimated as 1.79 and 2.04 mum(-1/2) for the same faces at same loads. Using Wooster's empirical relation, elastic stiffness coefficient, cll, has been calculated from hardness value. (C) 2001 Elsevier Science B.V. All rights reserved.

引用

页码：143 / 147

页数：5

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