کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
774826 1463740 2016 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
A numerical analysis of the mechanisms behind plasticity induced crack closure: Application to variable amplitude loadings
ترجمه فارسی عنوان
تجزیه و تحلیل عددی از مکانیزم های بسته شدن کرک ناشی از پلاستیک: کاربرد در بارهای دامنه متغیر
کلمات کلیدی
مکانیسم نوک کراک، بسته شدن کرک ناشی از پلاستیسیته، تغییر شکل پلاستیکی باقی مانده، نوک تیز نازک، بسته شدن جزئی
موضوعات مرتبط
مهندسی و علوم پایه سایر رشته های مهندسی مهندسی مکانیک
چکیده انگلیسی


• An analytical model was used to isolate the effect of residual deformation on PICC.
• Significant differences were obtained between model’s predictions and FEM results.
• Crack tip blunting explains the transient behaviour after overloads and load blocks.
• No evidences of Donald’s effect were found.

The effect of loading parameters on fatigue crack growth has been explained using the concept of crack closure. Plasticity induced crack closure (PICC) is linked to the crack tip plastic deformation, which becomes residual with crack propagation. The objective here is to identify the main mechanisms behind PICC, and for that different loading cases were considered namely overloads and load blocks. An analytical model was used to isolate the effect of residual plastic deformation on PICC, however significant differences were obtained relatively to finite element results. A second mechanism, which is crack tip blunting, was used to explain the transient behaviour observed after overloads and load blocks. For overloads and low–high load sequences there is a sudden increase of crack tip blunting with load increase which explains the sudden decrease of crack opening level. For high–low load sequences there is a sudden decrease of crack tip blunting which enhances the effect of residual plastic wake. Finally, the partial closure concept was tested looking to non-linear crack tip parameters but no evidences of Donald’s effect were found for the material studied.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: International Journal of Fatigue - Volume 89, August 2016, Pages 43–52
نویسندگان
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