Structure design and reliability analysis of Al-Ti lugs

铝钛复合耳片结构设计及可靠性分析

School of Aeronautics, Northwestern Polytechnical University, Xi'an 710072, China

Received: 1 July 2020

Abstract

Aircraft lug joint is the key part of load transfer. In order to improve the safety of lug joint, on the premise of meeting the design requirements of static strength and fatigue, the composite connection lug structure design technology of different metal materials is proposed in this paper. Firstly, the damage safety design and life reliability analysis of the lug structure are studied theoretically. Secondly, based on the concept of damage safety design and the design principle of deformation coordination, the design method of composite connection lug with deformation coordination is proposed, and the thickness ratio of single ear is 0.8:1:0.8. Finally, the reliability of the composite lug is analyzed. The results show that the structural design scheme of aluminum-titanium composite ear piece can meet the requirements of static strength and damage tolerance, and compared with the conventional ear structure, the failure probability of structure mission life is greatly reduced when the weight of the composite connection lug is only increased by 4.9%. The proposed method can effectively guide the structural design of composite ear piece.

摘要

飞机耳片接头是传递载荷的关键部位，为了提高耳片接头的安全性，在保证满足静强度、疲劳等设计要求的前提下，提出了不同金属材料复合连接耳片结构设计技术。对耳片结构从破损安全设计和寿命可靠性分析方面进行了研究；针对某飞机接头耳片，基于破损安全设计理念及变形协调设计原则，提出了复合连接耳片的设计方法，并依据所提方法确定了"铝-钛-铝"厚度比例为0.8：1：0.8单耳设计方案，进而开展了静力学、损伤容限设计及寿命可靠性分析。结果表明：所提出的铝钛复合耳片结构设计方案可满足静强度和损伤容限要求，且与常规耳片结构对比，复合耳片在质量仅增加4.9%的情况下结构任务寿命失效概率大幅降低。论文所提方法可用于指导复合耳片的结构设计。