【摘要】 对一种超塑性温度相对较低的双相钛合金SPZ的超塑性能进行了研究。结果表明:740~800℃,应变速率恒为1.11×10-3s-1时,SPZ合金的最大拉伸延伸率均超过1600%;760°C,合金的超塑延伸率可高达2149%。760℃,应变速率高达1.11×10-2s-1时,合金的超塑延伸率仍可达1380%。也就是说,700℃/1hAC处理后,SPZ合金在试验温度范围内具有低温高速超塑性。SEM观察发现,超塑变形前,合金的晶粒细小均匀,平均晶粒尺寸只有0.89μm;应变速率为2.22×10-3s-1,740℃,760℃变形后SPZ合金的晶粒尺寸分别为1.51μm,2.33μm。超塑性变形的微观机制是以晶界滑动为主,晶内变形以及位错蠕变起了协调作用。更多还原

【Abstract】 Microstructures and superplastic properties of one kind of α plus β typed titanium alloy were studied in this paper.The results indicated that the maximum tensile elongations are all over 1600% for the alloy deformed from 740℃ to 800℃ with the primary strain rate of 1.11×10^-3s^-1;and which is 2149% for the alloy deformed at 760℃.The elongation is up to 1380% for the alloy deformed at 760℃ with the primary strain rate of 1.11×10^-2s^-1,which means,the alloy annealed at 700℃ for 1h possess superior low temperature high strain rate superplastic property during the mentioned testing temperature range.The grain size is as small as 0.89μm before superplastic deformation;and which is 1.51μm and 2.33μm,respectively for the alloy deformed at 740℃ and 760℃ with the strain rate of 2.22×10^-3s^-1.The principal superplastic deformation mechanism for the alloy is boundary sliding,assistant ones are deformations inside the grains and dislocations creep.更多还原