A method for heat treating titanium-alloy articles in a vacuum furnace includes a step of first determining, for a first set of titanium articles in a first vacuum furnace and for a first set of heat treatment conditions, a minimum surface area of the first set of titanium articles associated with an acceptable alpha case formation for the first set of titanium articles. There is a second determining, for a second set of titanium articles in a second vacuum furnace and for a second set of heat treatment conditions, of a minimum surface area of a second set of titanium articles associated with an acceptable alpha case formation for the second set of titanium articles, responsive to the value of the minimum surface area of the first set of titanium articles. There follows a heat treating of a third set of titanium articles in the second vacuum furnace and for the second set of heat treatment conditions, where the surface area of the third set of titanium articles is not less than the value of the minimum surface area of the second set of titanium articles.