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为了挖掘亚稳β钛合金Ti-B19的热变形加工潜力,采用热模拟试验机,在温度范围750-1000°C,温度间隔50°C,应变速率为0.001-10s-1的条件下对Ti-B19合金的热压缩行为进行研究。结果表明,一定温度下,Ti-B19合金的流变应力随应变速率的增大而增大;一定应变速率下,合金的流变应力则随温度的升高而降低。当应变ε为0.6时,合金的加工图可分为3个区域。700-800°C,应变速率为0.001-0.1s-1,合金最大的能量耗散效率值出现在750°C和0.01s-1处,其数值为42%,出现连续软化之前,此区域的流变曲线中只出现单个峰或振荡峰。第2个区域的温度范围在800-1000°C,应变速率范围为0.001-0.1s-1,能量耗散效率值在29%～36%之间变化。此区域的流变曲线到达稳态之前只出现单个峰或振荡峰,此时可观察到典型的再结晶组织。温度低于800°C,应变速率大于0.1s-1,或者温度高于800°C,应变速率大于10s-1时,合金中会出现典型的流变不稳定的第3区,组织中可观察到绝热剪切带或β相流变不均匀区。
Ti-B19 in order to tap the thermal deformation of the potential processing, the use of thermal simulation test machine, in the temperature range of 750-1000 ° C, the temperature interval of 50 ° C, the strain rate of 0.001-10s-1 conditions Ti B19 alloy hot compression behavior of the study. The results show that the flow stress of Ti-B19 alloy increases with the increase of strain rate at a certain temperature. The flow stress of the alloy decreases with the increase of temperature at a certain strain rate. When the strain ε is 0.6, the alloy processing diagram can be divided into three regions. 700-800 ° C, the strain rate of 0.001-0.1s-1, the maximum energy dissipation efficiency of the alloy occurs at 750 ° C and 0.01s-1, the value of 42%, before the continuous softening of the region Only one single peak or oscillation peak appears in the rheological curve. The second region has a temperature range of 800-1000 ° C, a strain rate range of 0.001-0.1 s-1, and an energy dissipation efficiency of 29% -36%. Only a single peak or oscillation peak appears before the rheological curve in this region reaches the steady state, and typical recrystallized structure can be observed. At temperatures below 800 ° C, strain rates greater than 0.1 s-1, or temperatures above 800 ° C, the strain appears to be characteristic of a region of instability, Region 3, at a strain rate greater than 10 s-1, observable in the tissue To adiabatic shear zone or non-uniform zone of β-phase flow.