300M钢耳片拉伸强度与破坏机制  

Tensile Strength and Failure Mechanism of 300M Steel Lugs

作　　者：周忠义 徐武[1] 陆冠 刘天兴 ZHOU Zhongyi;XU Wu;LU Guan;LIU Tianxing(School of Aeronautics and Astronautics,Shanghai Jiao Tong University,Shanghai 200240,China;Shanghai Aircraft Airworthiness Certification Center of Civil Aviation of China,Shanghai 200335,China;AVIC First Aircraft Design and Research Institute,Xi'an 710089,China)

机构地区：[1]上海交通大学航空航天学院,上海200240 [2]中国民用航空上海航空器适航审定中心,上海200335 [3]航空工业第一飞机设计研究院,西安710089

出　　处：《机械设计与研究》2022年第5期225-231,237,共8页Machine Design And Research

摘　　要：耳片是连接飞行器不同部位的关键零件,提升耳片的强度和准确计算不同耳片的承载能力对飞机减重和保证飞行安全具有重要意义。300M钢耳片由于强度高、韧性好在飞机起落架中得到了越来越广泛的应用。然而,我国《飞机设计手册》中并没有给出准确计算300M钢耳片拉伸强度的效率系数,也不清楚各种耳片失效模式的原因。为此,设计了不同形式和几何尺寸的耳片,开展了不同加载角度拉伸破坏试验,获得了耳片拉伸极限载荷和破坏模式。在此基础上,给出了300M钢耳片拉伸强度效率系数的计算公式,建立并验证了300M钢耳片拉伸极限载荷分析的弹塑性有限元方法,仿真预测的极限载荷误差小于8%。结合试验结果揭示了300M钢耳片的破坏机制,基于J_(2)弹塑性本构模型和临界等效塑性应变断裂准则,开发VUMAT子程序模拟了3种典型断裂路径。Lug is a critical element connecting different parts of the aircraft.Improvement and accurate prediction of the tensile strength of lugs is of great significance for weight reduction and aircraft safety.300M steel lugs have been more and more widely used in aircraft landing gears due to their high strength and good toughness.However,Chinese"Aircraft Design Manual"does not provide precise engineering method for calculating the tensile strength of 300M steel lugs.In addition,the mechanism of different failure modes of lugs is unclear.Therefore,lugs of different shapes and dimensions are designed and tested to obtain their ultimate tensile strength.On this basis,the equations for calculating the engineering coefficient of the tensile strength of 300M steel lug is given,and the elastic-plastic finite element method for analyzing the ultimate tensile load of 300M steel lug is established and verified,with a prediction error of less than 8%.Combined with the test results,this paper reveals the failure mechanism of the 300M steel lug.Furthermore,based on the J_(2),elastoplastic constitutive model and the fracture criterion for when equivalent plastic strain meets critical value,a VUMAT subroutine is developed to analyze three typical fracture paths.The simulation results are in good agreement with the tests.

关 键 词：300M钢耳片设计 拉伸强度 破坏机制 弹塑性有限元方法 断裂路径 

分 类 号：V229.1[航空宇航科学与技术—飞行器设计]