Ti-Al层状复合板Ⅱ型层间断裂关键参量研究

Research on key parameters of Ⅱ interlaminar fracture of Ti-Al laminated composite plate

采用端边切口三点弯曲试验(3ENF)方法,分析了试样宽度、试样长度、预制裂纹长度和弯曲模式对载荷-位移变化的影响规律;优化了3ENF合理的试样尺寸,具体参数为长70 mm,宽5 mm,预裂纹长度25 mm,钛层在弯曲外侧;获得了合理试样尺寸下Ti-Al层状复合板3ENF的力-位移曲线;基于优化的试样尺寸获得了Ti-Al层状复合板界面切向应力最大值τmax和界面开裂特征位移δt两个关键参数的合理值,分别为124.1 MPa和10.9 mm。研究结果为后续采用有限元方法研究Ti-Al层状复合板冷塑性成形过程中界面分层损伤失效行为提供了重要数据支撑。

The effect law of specimen width,specimen length,prefabricated crack length and bending mode on the load-displacement variation was analyzed by means of the single edge crack three point bending test(3ENF).The reasonable specimen size of 3ENF was op-timized,which were 70 mm in length,5 mm in width,25 mm in pre-crack length and the titanium layer bended on the outside.The force-displacement curves of 3ENF of Ti-Al laminated plate with reasonable specimen size were obtained.Based on the optimized speci-men size,the reasonable values of two key parameters,the maximum tangential stressτmax of 490 MPa and the characteristic displacementδt of 10.9 mm,at the interface of Ti-Al laminated composite plate were obtained by calculation respectively.The research results provide an important data support for the subsequent study of the interfacial delamination damage and failure behavior of Ti-Al laminated plate dur-ing cold plastic forming by finite element method.