小冲杆试验中韧性断裂的实验与计算研究

Experimental and Computational Study of Ductile Fracture in Small Punch Tests.

作者信息

Gülçimen Çakan Betül, Soyarslan Celal, Bargmann Swantje, Hähner Peter

机构信息

Department of Mechanical Engineering, Uludağ University, Görükle, 16059 Bursa, Turkey.

Nuclear Safety and Security Directorate, Joint Research Centre, European Commission, NL-1755 LE Petten, The Netherlands.

出版信息

Materials (Basel). 2017 Oct 17;10(10):1185. doi: 10.3390/ma10101185.

DOI:10.3390/ma10101185

PMID:29039748

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC5666991/

Abstract

A unified experimental-computational study on ductile fracture initiation and propagation during small punch testing is presented. Tests are carried out at room temperature with unnotched disks of different thicknesses where large-scale yielding prevails. In thinner specimens, the fracture occurs with severe necking under membrane tension, whereas for thicker ones a through thickness shearing mode prevails changing the crack orientation relative to the loading direction. Computational studies involve finite element simulations using a shear modified Gurson-Tvergaard-Needleman porous plasticity model with an integral-type nonlocal formulation. The predicted punch load-displacement curves and deformed profiles are in good agreement with the experimental results.

摘要

本文提出了一项关于小冲头试验中韧性断裂起始与扩展的统一实验-计算研究。试验在室温下对不同厚度的无缺口圆盘进行，其中大规模屈服占主导。在较薄的试样中，断裂发生在膜张力下的严重颈缩，而对于较厚的试样，贯穿厚度的剪切模式占主导，改变了裂纹相对于加载方向的取向。计算研究包括使用具有积分型非局部公式的剪切修正古尔森-特弗加德-内德曼多孔塑性模型进行有限元模拟。预测的冲头载荷-位移曲线和变形轮廓与实验结果吻合良好。