Metastable beta titanium alloys have emerged as a subject of intense research in the last three to four decades. They are epitomized by heat treatability to high strength, high hardenability, and excellent workability. Heat treatment comprises solution treating and aging. In the recent years, there has been much interest in carrying out aging in two steps, rather than in a single step. Duplex aging on different grades of beta alloys resulted in improved microstructure and better combination of mechanical properties. Duplex aging suppresses formation of grain boundary alpha and eliminates precipitate-free zones, leading to improved ductility and fatigue life. There is thus a strong case to adopt duplex aging. A low heating rate to aging temperature may be tantamount to duplex aging. There are a few grades, where duplex aging impairs ductility, becoming counterproductive. The paper reviews the subject of duplex aging of metastable titanium alloys.

在过去的三到四年里，亚稳态 β 钛合金已成为一项深入研究的主题。它们以高强度、高淬透性和优异的可加工性的热处理性为代表。热处理包括固溶处理和时效。近年来，人们对分两步进行老化很感兴趣，而不是一步。不同等级 β 合金的双相时效改善了微观结构和更好的机械性能组合。双相时效抑制晶界α的形成并消除无沉淀区，从而提高延展性和疲劳寿命。因此，有充分的理由采用双工老化。对老化温度的低加热速率可能等同于双重老化。有几个等级，双相时效会损害延展性，变得适得其反。本文回顾了亚稳态钛合金的双重时效问题。