Study of the Inert-Gas Arc Welding of Titanium and its Alloys (4th Report)

Effect of the Alloying Elements and Heat Treatments on the Properties of Titanium Alloys

Abstract

In this investigation, were studied how the properties were changed when various composition of titanium alloys were heat treated (heating and tempering), in order to study the composition ranges of strong titanium alloys.
Consequently, found that rather much alloying element, for example 7-15%Mn, must be added to titanium so as to obtain strong titanium alloys. And to strengthen still more these and other titanium alloys (α+β titanium alloys containing a small amount of β-stabilizer, such as 2%Al-2%Mn-Ti alloy), the alloy have only to be quenched from over (β)/(α+β) transformation temperature according to their composition.
The structure in strong titanium alloys obtained with above method are as follows :
1) Serrated α(α') in α titanium alloys.
2) Acicular α(α')+β in α+β titanium alloys containing a small amount of β-stabilizer.
3) β+fine α' or β only in α+β titanium alloys containing a large amount of β-stabilizer.
And the hardness in these titanium alloys was Hv. 400 to 550.