热处理对BT36高温钛合金组织及性能的影响

The effect of heat treatment on microstructure and properties of BT36 high temperature alloy

BT36是俄罗斯研制的一种600℃高温钛合金,该合金的特点之一是含5%左右的W。本文采用BT36轧棒(20mm)研究了5种不同的热处理制度,进行了金相组织分析和性能测试(包括拉伸、蠕变、热稳定性等)。结果表明,获得片层组织是提高合金600℃持久及蠕变性能的关键,而且需要依靠适当的热处理工艺控制片层的厚度及形貌。BT36棒材通过5重热处理(995℃ 0.5h,AC+970℃ 2h,FC→700℃ 2h,AC+500℃ 15h,AC+650℃ 6h,AC)可获得较好的综合性能。

BT36 is a high temperature titanium alloy designed to be served at 600℃ in Russia. This alloy contained 5% W, were subjected to five heat treatment processes, and the optical microstructure and mechanical properties (including tensile property, creep resistance, thermal stability, etc) have been examined. The results show that the transformed structure from β phase is one essential factor of high creep resistance, since it's important to control α plate thickness and morphology of transformed β structure by heat treatment process. The fivefold heat treatment process (995℃/0.5h,AC+970℃/2h left in furnace, and cooling to 700℃/2h,AC+500℃/15h,AC+650℃/6h,AC) is preferable for optimum mechanical properties.