Damage evolution in aluminum alloys and composites under dynamic/shock loading

动态/冲击载荷下铝合金和复合材料的损伤演变

• 批准号: 371459-2010
• 负责人: Odeshi, Akindele
• 金额: $ 1.6万
• 依托单位: University of Saskatchewan
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2014
• 资助国家: 加拿大
• 起止时间: 2014-01-01 至 2015-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=550048
• 关键词: Damage; evolution; aluminum; alloys; composites

Aluminum alloys and aluminum-based composites are finding very useful applications in the defense, automobile and aerospace industries as a result of their high strength-to-weight ratio. The use of aluminum alloys as armor plates has continued to attract increased attention in the military in order to improve the efficiency of military combat vehicles. A proper evaluation of how armor plates behave under extreme loading condition as in ballistic impact or exposure to improvised explosive devices (IED), as currently being witnessed by Canadian Armed forces, is a key factor to ensuring the safety of military personnel in peace keeping operations. The aluminum alloy frames of aircrafts must also be able to withstand the threat of exposure to shock loading as exemplified by impact from extraneous object during flight. As in the case of the other metallic alloys, failure of aluminum alloys under shock or impact loading is initiated by extreme localization of deformation along narrow bands called adiabatic shear bands. Occurrence of adiabatic shear bands in high performance aluminum alloys reduces their capacity to resist perforation or cracking during high velocity impact. This research program involves a systematic investigation of the damage evolution in aluminum alloys under shock loading in relation to the occurrence of adiabatic shear bands, as influenced by the alloy composition, temper and loading conditions, and ceramic particle reinforcement. Optimized microstructure design for an enhanced capacity to withstand adiabatic shear failure under impact loading is the aim of this study. The dynamic stress-strain data that will be used in developing microstructure-sensitive numerical simulation of the impact response of the materials will be generated. The development of enhanced constitutive models suitable for progressive damage analysis of aluminum alloys and composites that takes into account the materials' non-linearity and strain-rate effects, which are associated with shock loading is a long term goal of this research program. This approach will provide information on how to tailor aluminum alloy's properties in order to improve their dynamic impact behaviour.

铝合金和铝基复合材料由于其高的强度重量比而在国防、汽车和航空航天工业中得到非常有用的应用。为了提高军用战斗车辆的效率，铝合金作为装甲板的使用在军事上持续引起越来越多的关注。正如加拿大武装部队目前所看到的那样，对装甲板在弹道冲击或暴露于简易爆炸装置等极端载荷条件下的行为进行适当评估，是确保维持和平行动中军事人员安全的一个关键因素。飞机的铝合金框架还必须能够承受暴露于冲击载荷的威胁，例如在飞行期间来自外部物体的冲击。与其他金属合金一样，铝合金在冲击或冲击载荷下的失效是由沿着称为绝热剪切带的窄带的变形的极端局部化引起的。高性能铝合金中绝热剪切带的出现降低了其抗高速冲击穿孔或开裂的能力。该研究计划涉及到在冲击载荷下的绝热剪切带的发生，受合金成分，回火和加载条件，和陶瓷颗粒增强的影响，在铝合金的损伤演化的系统调查。优化的微观结构设计，以增强承受冲击载荷下的绝热剪切破坏的能力是本研究的目的。动态应力-应变数据将用于开发材料冲击响应的微观结构敏感数值模拟。本研究的长期目标是发展适用于铝合金和复合材料渐进损伤分析的增强型本构模型，该模型考虑了与冲击载荷相关的材料非线性和应变率效应。这种方法将提供有关如何定制铝合金的性能，以改善其动态冲击行为的信息。