不同组织TA15钛合金热压缩力学行为研究

采用gleeble-1500 热模拟试验机,对TA15钛合金4种典型组织试样进行了高温准静态压缩试验,研究了不同原始组织的TA15钛合金高温压缩力学行为,不同组织对其高温准静态力学性能及温度敏感性的影响.结果表明:在同一温度下,4种组织的流变应力随温度的升高而降低,且最初流变应力随应变的增加快速增加,当流变应力达到一个峰值后,逐渐下降,最后处于稳定流变状态;不同的组织对TA15钛合金高温准静态力学性能有很大影响;600 ℃变形时,网篮组织的温度敏感性最低,固溶时效组织其次,双态组织第三,等轴晶粒组织温度敏感性最高;700~900 ℃下变形,各组织温度敏感性的排序不变,但网篮组织的温度敏感性和其它3种组织温度敏感性的差距缩小;当在超过相变温度的1000 ℃下变形时,各试样的组织完全相同,其温度敏感性不再有任何差异,其力学性能也几乎相同.

Research on hot compression mechanical behavior of TA15 titanium alloy with different microstructure

Using the gleeble-1500-type thermal simulation testing machine,high temperature quasi-static compression test on four kinds of typical original microstructure of the TA15 titanium alloy has been done.Effects of original structure on hot deforming behavior,mechanical properties and temperature sensitivity of TA15 titanium alloy has been studied by connecting the hot deforming behavior of kinds of typical original microstructure of the TA15 titanium alloy and the corresponding metallographic analysis.It is shown that the flow stress decreases with increasing temperature at the same temperature,the flow stress rapidly increases with the increasing strain at the beginning stage of deformation.When the flow stress reaches a maximum value,then it will reduce gradually and reach a stable state finally.The microstructure has a great effect on high temperature quasi-static mechanical properties of TA15 titanium alloy.Deforming at 600 ℃,the sequence of temperature sensitivity in descending order is equiaxed structure,binary structure,solution and aging structure and lamellar structure.Deforming between 700 ℃ and 900 ℃,the order of temperature sensitivity is not changed,but the gap between the temperature sensitivity of lamellar structure and other three kinds of structure become diminution.When the deforming temperature is above phase transition temperature,the temperature sensitivity and mechanical properties of all kinds of microstructure become identical because its structure is same due to phase transition.