【摘要】 本文采用光学金相、电子金相、电子衍射、硬度测量及光学膨胀试验等方法,研究了Ti-6.5Al-3.5Mo-2Zr-0.25Si(BT9)合金的等温转变过程,建立了它的自1020℃(β相区)固溶而后过冷到不同温度的等温转变图,确定了等温温度、转变产物的组织形态和机械性能(室温拉伸)之间的关系;并初步探讨了BT9合金等温转变的机理。试验还证明,钛合金的马氏体转变开始点M,与过冷β相的冷却速度有关,冷速愈快,M_s点愈低。更多还原

【Abstract】 In this paper, the isothermal transformation process of titanium alloy Ti -6.5Al-3.5Mo-2Zr-0.25Si (BT9) was investigated by the means of metallurgical and electron microscopy ( TEM ), electron diffraction,optical dilatometry and hardness test. Based on the results of investigation, we established the T.T.T diagram of BT9 alloy and the relationship between its morphology of structure and mechanical properties. Furthermore, the mechanism of isothermal transformation of BT9 alloy was studied sketchily. In our tests, we have still proved that the start temperature of martensite transformation (M,) of titanium alloy varies with cooling rate of β-phase, the higher the cooling rate, the lower the Ms.更多还原