Abstract

Damage is a progressive physical process that results in fracture. Recently, study of damage and failure in materials, particularly ductile metals has been of great importance for mechanical and structural engineers. So far, numerous criteria have been presented to predict damage behavior in ductile metals, each criterion is known by its advantages, disadvantages, and accuracy. One of the most famous models has been proposed by Lemaitre which is an accurate model and requires only one parameter to attain damage behavior of materials. In this article, employing the Lemaitre's ductile damage criterion, a new explicit, simple, and quick method is suggested to numerically determine the Lemaitre's damage parameter and damage behavior of ductile metals. This approach is much easier and cheaper than former conventional experimental methods because only needs a simple standard tensile test. Accuracy of the current numerical approach is validated through the experimental tests such as the standard, single and double notched tensile tests, and also the Nakazima fracture test. The numerical simulation results show suitable accuracy together with negligible percentage of error and perfect correlation in comparison with the experimental results.

摘要

损伤是导致骨折的渐进物理过程。最近，研究材料（尤其是延展性金属）的损坏和失效对于机械和结构工程师来说非常重要。到目前为止，已经提出了许多标准来预测延展性金属的损伤行为，每个标准都有其优点、缺点和准确性。Lemaitre 提出了最著名的模型之一，这是一个精确的模型，只需要一个参数即可获得材料的损伤行为。在本文中，采用 Lemaitre 延性损伤准则，提出了一种新的明确、简单、快速的方法来数值确定 Lemaitre 损伤参数和延性金属的损伤行为。这种方法比以前的传统实验方法更容易、更便宜，因为只需要一个简单的标准拉伸测试。当前数值方法的准确性通过标准、单缺口和双缺口拉伸试验以及 Nakazima 断裂试验等实验测试得到验证。与实验结果相比，数值模拟结果显示出合适的精度以及可忽略的误差百分比和完美的相关性。