کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1448920 988687 2010 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Tensile and compressive behavior of tungsten, molybdenum, tantalum and niobium at the nanoscale
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد سرامیک و کامپوزیت
پیش نمایش صفحه اول مقاله
Tensile and compressive behavior of tungsten, molybdenum, tantalum and niobium at the nanoscale
چکیده انگلیسی

In situ nanomechanical tests are carried out to investigate the tensile and compressive behavior of 〈0 0 1〉-oriented body-centered cubic (bcc) metals W, Mo, Ta and Nb with nanometer dimensions. We find that the strength of these metals exhibits strong size dependence. The compressive size effect in Nb, as evaluated by the log–log slope of strength vs. nanopillar diameter, is −0.93, a factor of 2.1 greater than that for the other three metals W, Mo and Ta (−0.44). In tension, however, Ta and Nb show higher size effect slopes (−0.80 and −0.77) as compared with W and Mo (−0.58 and −0.43). We also report that while the yield strength of these metals is a strong function of size, the strain-hardening behavior does not present any size-dependent trends. We further discuss the effects of strain-rate on deformation behavior and provide transmission electron microscopy analysis of microstructural evolution in the same Mo nanopillar before and after compression.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Acta Materialia - Volume 58, Issue 7, April 2010, Pages 2355–2363
نویسندگان
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