钛合金蜂窝平板声载-静载联合加载设计与试验

Acoustic-static Combined Loads Design and Test on Titanium Alloy Honeycomb Acoustic Liners

为考察钛合金蜂窝声衬在噪声载荷与气动压力联合作用环境下的疲劳特性,根据蜂窝声衬的受载特征,提出了一种声载-静载联合试验方法,利用大气与真空舱之间的压力差来实现声衬的等效气动力加载,设计并制造了抽真空机械组件对试件非受声面抽真空,解决了行波管中施加静力载荷难的问题。针对两类高度不同的钛合金蜂窝声衬平板件,开展了10 h的声载-静载联合疲劳试验。试验结果表明:两类钛合金蜂窝声衬试件一阶共振频率均没有发生的明显变化,说明试件的整体刚度在试验前后没有发生改变。无损检测结果表明:蜂窝芯较高的钛合金声衬平板试件中部分出现了局部脱焊。

In order to investigate the fatigue characteristics of the titanium alloy honeycomb acoustic liner under the combined loads of noise and aerodynamic pressure,a combined test method of acoustic load and static load was proposed based on the load characteristics of the honeycomb acoustic liner.The equivalent aerodynamic load of the liner was realized by using the pressure difference between the atmosphere and the vacuum tank,and the vacuum pumping device was designed and manufactured to vacuum the non-acoustic surface of the specimen,which solved the problem of loading static pressure in traveling wave tube.Then 10 hours of sonic-static combined fatigue tests on two kinds of titanium alloy honeycomb acoustic liners with different height were carried out.The results show that the first-order resonance frequency of the two kinds of titanium alloy honeycomb acoustic liner specimens does not change significantly,which means the overall rigidity of the specimens does not change.However,the non-destructive inspection results show some of the titanium alloy honeycomb acoustic liner specimens with higher honeycomb cores appeare some local welding-off areas.