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Premature failure of titanium based engineering components in the 1970s brought to attention the phenomenon of dwell effects at low temperatures in these alloys, loosely termed „cold creep‟, which are currently still a major concern for designers. These failures were characterised by the formation of quasi-cleavage facets thought to be a result of extended dwell periods. However, the particular conditions under which these facets form is still not fully understood, leading to the necessity of above average safety factors in material lifing that could be reduced through increased understanding.
The current paper seeks to address the issue through exploring the results of a series of targeted tests in the titanium alloys Ti6-4, Ti685 and Ti834. The presence, extent and effect on mechanical properties of these features are investigated with conclusions made about the loading conditions under which formation occurs. The resultant effect on both creep and fatigue life is also studied through a series of comparisons.