کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1449437 988704 2007 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
The hardness of silicon and germanium
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد سرامیک و کامپوزیت
پیش نمایش صفحه اول مقاله
The hardness of silicon and germanium
چکیده انگلیسی

It is generally accepted that the hardness of silicon and germanium at low temperature is limited by a phase transformation under the indenter, as the measured hardness is equal to the transformation pressure. However, observations of the deformation under indents using transmission electron microscopy indicate that, in addition to the phase transformation, there is also plastic flow both in the transformed region and outside it. An analysis based on the spherical cavity model for indentation was developed to quantify the effect of a phase transformation on the measured hardness. This predicts that plastic deformation will extend beyond the transformed zone when the transformation pressure is greater than two-thirds of the yield stress. The analysis also predicts that the hardness can only be approximately equal to the transformation pressure if the yield strength of the transformed material is low, consistent with the experimental observations of substantial plastic deformation of the transformed phase, as well as with estimates of its lattice resistance.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Acta Materialia - Volume 55, Issue 18, October 2007, Pages 6307–6315
نویسندگان
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