不同材质航空用沉头铆钉装配数值模拟

Numerical Simulation on The Aviation Countersunk Rivet Assembly Using Different Aviation Materials

铆接在飞机装配中占有重要的地位,2017铝合金和Ti45Nb钛合金是目前常用的铆钉材料。为研究两种铆钉装配后铆钉及被连接板应力应变的异同,参照实际生产中的尺寸参数,建立了沉头铆钉装配过程的有限元模型,通过最大压铆力验证了模型的准确性。结果表明,Ti45Nb钛合金铆钉残余应力和塑性应变值均明显大于2017铝合金铆钉,产生了更为严重的应力集中,其疲劳问题更应引起关注。此外,Ti45Nb钛合金铆钉相较2017铝合金铆钉还使被连接板产生了更高的应力应变,应注意其对铆接结构刚度和应力腐蚀开裂等问题的影响。

Riveting plays an important role in aircraft assembly.At present,2017 aluminum alloy and Ti45Nb titanium alloy are commonly used as rivet materials.In order to study the similarities and differences of stress and strain in rivets and riveting plates between two kinds of rivet,AFE(Finite Element Analysis)model of the assembly process of countersunk rivet was established based on the actual production.The accuracy of the model is verified by the consistence between the model and actual maximum riveting force.Results show that the residual stress and plastic strain values of Ti45Nb titanium alloy rivets are significantly higher than those of 2017 aluminum alloy rivets,and the stress concentration of the Ti45Nb titanium alloy rivets shows superiorly severe,thus the fatigue problem of Ti45Nb titanium alloy rivets should be paid more attention.In addition,Ti45Nb titanium alloy rivets make plates have a higher stress and strain than the 2017 aluminum alloy rivets,which may affect the stiffness and stress corrosion cracking of the riveted structure.