【摘要】 利用X射线衍射技术对冷轧制备的TA18钛合金航空管材沿壁厚内、中、外3层的织构进行测定与分析,还测试了由织构决定、且能反映管材各向异性特性的收缩应变比(contractile strain ratio,CSR)。结果表明:管材织构强度沿层深会形成较大的梯度变化,通过晶体取向分布函数(ODF)的峰值密度显示的织构梯度变化大于17%,特别是各层的织构的类型也存在很大差别。仅采用减薄展平法取管材中层织构评定管材性能时,即使织构强度等级较高,也会出现CSR下降的情况,原因在于,管材存在沿层深不一致的织构分布,出现有利的径向织构和不利的切向织构共存的情况,不利织构分数过大,将导致其CSR值降低。确定织构沿层深的分布为进一步预测并改进管材的力学性能提供参考,并为改善生产工艺提供依据。更多还原

【Abstract】 The texture of the inner layer, middle layer and outer layer of cold rolled TA18 alloy tube were investigated and analyzed by X-ray diffraction technique. Contractile strain ratio(CSR), determined by the texture, which can reflect mechanical property anisotropy of a tube was also tested. The results show that texture intensity has a big gradient along the tube wall; through the peak value of orientation density from the orientation distribution function(ODF), the variation gradient is over 17%, and texture types are different greatly among the layers. The texture of the middle layer measured by the method of thinning and flattening, although it is high for this tube, its CSR is only 0.95, less than that of use standard 1.3. It is due to that the texture is not uniform along the tube wall, there exists favorable texture in radial direction and negative texture in tangential direction, and strong negative texture leads to deterioration of the mechanical property. Confirming the distribution of texture along the tube wall can provide reference for forecasting and improving mechanical properties of the tube, and supply foundation to optimize production process.更多还原