Growth mechanism of αp and interface relationships between αp and αs during cooling of a near α titanium alloy

•The rapid cooling rate facilitates the precipitation of the secondary αs.•The low cooling rate is conducive to the epitaxial growth of the primary αp.•The preferential growth of αGB can be independent of the BOR effect.•The common {1 1 2¯ 0} and {1 0 1¯ 0} plane are shared by primary αp and precipitation αs to reduce the interface energy.