Multi-point forming of sandwich panels with egg-box-like cores and failure behaviors in forming process: Analytical models, numerical and experimental investigations
Multi-point forming of sandwich panels with egg-box-like cores and failure behaviors in forming process: Analytical models, numerical and experimental investigations
复制标题
蛋盒状芯材夹芯板的多点成形及成形过程中的失效行为：分析模型、数值和实验研究。
DOI：
10.1016/j.matdes.2018.10.037
复制
发表时间：
2018-12-15
影响因子：
8.4
通讯作者：
Liang, Xiao-Bo
中科院分区：
文献类型：
--
作者：
Cai, Zhong-Yi;Zhang, Xi;Liang, Xiao-Bo
异形夹层部件的制造是一项具有技术挑战的任务。在本文中，研究了从最初平坦的夹层板生产双曲面面板的机械可行性。多点成形（MPF）和有限元分析实验结果表明，蛋盒型（EBL）芯材夹芯板塑性成形过程中的成形性能主要由面板塑性起皱、面板塑性凹坑和芯材单元断裂等失效模式主导。开发了预测面板屈曲的分析模型，并将起皱的极限弯曲半径和凹坑的临界应力确定为夹层板的几何参数和材料特性的函数。提出了基于应力的断裂极限曲线和预测核心单元断裂的相关理论公式。开发的分析模型已经过实验和有限元模拟的验证。进行了多点成形实验，最终论证了利用塑性成形技术成形EBL夹芯板的可行性。 (C) 2018 Elsevier Ltd. 保留所有权利。
The manufacturing of shaped sandwich components is a task with technical challenge. In this paper the mechanical feasibility to produce a doubly curved panel from an initially flat sandwich plate was investigated. Experimental results of multi-point forming (MPF) and finite element analyses reveal that the formability of sandwich panel with egg-box-like (EBL) cores in plastic forming process is mainly dominated by the failure modes of face sheet plastic wrinkling, face sheet plastic dimpling and core cell fracture. Analytical models for predicting the face sheet buckling were developed, and limit bending radius for wrinkling and the critical stress for dimpling were determined as the functions of the geometric parameters and material properties of sandwich plate. The stress-based fracture limit curve and associated theoretical formulations to predict the core cell fracture were presented. The developed analytical models have been validated experimentally and using finite element simulations. Multi-point forming experiments were carried out and the feasibility of using plastic forming technique to form EBL-cored sandwich panels was demonstrated finally. (C) 2018 Elsevier Ltd. All rights reserved.