高可靠度TC17基复合材料叶环破裂转速预测技术研究

High Reliability Burst Rotating Speed Prediction Technology of TC17 Matrix Composite Bling

关键词:  复合材料  叶环  破裂试验  评定准则  可靠度

Key words:  Composite  Bling  Burst test  Evaluation criteria  Reliability

摘要:

为了建立安全可靠预测TC17基复合材料叶环破裂转速的方法，尽快实现其工程应用，开展了SiC连续纤维增强TC17基复合材料叶环结构破裂转速预测技术研究。测定了复合材料叶环成型过程所导致的TC17基体力学性能变化规律，仿真分析了由于热不匹配导致的热残余应力对复合材料叶环强度的影响。考虑复合材料试棒和叶环结构的差异，建立了基于复合材料试棒拉伸强度极限的高可靠度复合材料叶环破裂转速预估准则。完成了复合材料叶环强度试验件设计、制备和试验验证，并对试验件进行了断口分析。结果表明：复合材料叶环成型后，TC17基体合金本构模型将发生改变，其屈服和拉伸强度都有较大程度的下降，强度分析时应予以考虑。复合材料叶环成型工艺所导致的叶环热残余应力使得复合材料增强芯的同一半径处的周向应力沿轴向产生了梯度，其周向和径向最大应力均有明显降低，还导致叶环残余变形最大位置发生了变化。在旋转试验过程中，应变实测值与仿真结果相近。断口分析结果证明本文研究的复合材料叶环结构实际破裂模式为周向破裂，与所建立的仿真方法和评估准则预测的破裂模式一致，且破裂转速的预测精度较高，并保证了设计的安全性，可满足工程应用需求。

Abstract:

In order to establish a safe and reliable method for predicting the burst speed of TC17 matrix composite bing and realize its engineering application as soon as possible， burst speed prediction technology of SiC continuous fiber reinforced TC17 matrix composite bling was researched. The law of changes of TC17 matrix mechanical properties caused by composite bling forming process was tested. Thermal residual stress caused by thermal mismatch between matrix and fiber on strength of composite bling was emulated. Considering the structural differences of composite test bar and bling， the predication criterion of high reliability burst speed of composite bling was established based on composite test bars tensile limit. The design， manufacture， and experiment of composite bling strength test piece were completed and burst analysis was carried out. The results show that the TC17 matrix constitutive model is changed and the yield strength and tensile strength decreased greatly after composite bling forming， and its influence should be considered. Thermal residual stress caused by composite forming process causes the hoop stress of the composite reinforced core to produce a gradient along the axial direction at the same radius， and the maximum stress in the hoop and axial directions decreases significantly， and cause the maximum position of residual deformation of the bling to migrate. During the rotation test， the measured strain value was similar to the simulation result. Burst analysis results prove that the actual burst mode of the composite bling designed in this paper is circumferential burst， and it is consistent with the established simulation method and evaluation criteria， and the prediction accuracy of burst speed is relatively high. The composite bling strength design is safe and can meet the needs of engineering application.