Bridging the scales: from the toughness of small specimens to the damage tolerance of large aerospace panels

商用飞机的主要结构部件采用碳纤维增强塑料(CFRP)，因此需要对这些材料的力学响应进行预测，包括失效和损伤容限。准确预测故障和损害容忍度的困难既在于故障过程的复杂性，也在于故障发生的规模。事实上，必须分析失效的尺度(微米)比典型的航空部件尺度(米)小得多，众所周知，强度和韧性取决于部件尺寸。本建议将通过关注三个挑战来解决上述问题。首先，该项目将评估这些复合材料在对抗破坏整个面板的裂纹扩展方面的坚韧程度(混合型跨层流断裂韧性)。接下来，我们将详细研究失效过程，以便开发出合适的微观力学模型。最后，该项目将专注于开发计算机代码，以帮助工程师更有效地设计复合材料部件。

The introduction of Carbon Fibre Reinforced Plastics (CFRP) for major structural parts in commercial aircraft leads to the need to predict the mechanical response, including failure and damage tolerance for these materials. The difficulty in predicting accurately failure and damage tolerance lies both on the complexity of the failure processes and in the scale at which they occur. In fact, the scales at which failure must be analysed (micro meters) are much smaller than the typical aerospace component scale (metres), and it is well known that strength and toughness depend on component size.This proposal will address the above, by focusing on three challenges. Firstly, the project will assess how tough these composites are at opposing the propagation of cracks which break entire panels (mixed mode translaminar fracture toughness). In continuation, the failure processes will be looked at in detail, so that suitable micromechanical models may be developed. Finally, the project will focus on developing computer codes which will assist Engineers in more effectively designing composite components.