Additive manufacturing methods

An additive manufacturing method comprising:

• using titanium, titanium hydride, aluminum, and vanadium additive manufacturing feedstock in forming an object by additive manufacturing, the object having a first microstructure;
• after completing a shape of the object, heat treating the object between about 600 and about 1,000° C.;
• cooling the heat treated object;
• and
• dehydrogenating the cooled object under vacuum between about 500 and about 1,200° C., the completed shape containing about 0.5 to about 1.2 weight % hydrogen before the dehydrogenating and the dehydrogenated object having a second microstructure exhibiting finer and more uniform structure compared to the first microstructure such that the dehydrogenated object exhibits a size of alpha colonies, in the smallest dimension of the alpha colonies, of less than about 25 microns and an acicular alpha phase width, in the smallest dimension of the acicular alpha phase in the alpha colonies and in grain boundaries, of less than about 10 microns.

An additive manufacturing method comprising:

• forming an object containing Ti-6Al-4V by additive manufacturing, the object having a first microstructure containing columnar structures along a build direction of the additive manufacturing and the object exhibiting mechanical property anisotropy resulting from the columnar structures;
• after completing a shape of the object, hydrogenating the Ti-6Al-4V using hydrogen-containing gas;
• heat treating the object containing the hydrogenated titanium between about 600 and about 1,000° C.;
• and
• dehydrogenating the heat treated object under vacuum between about 500 and about 1,200° C. and reducing mechanical property anisotropy, the completed shape containing about 0.5 to about 1.2 weight % hydrogen before the dehydrogenating and the dehydrogenated object having a second microstructure exhibiting finer structure compared to the first microstructure such that the dehydrogenated object exhibits a size of alpha colonies, in the smallest dimension of the alpha colonies, of less than about 25 microns and an acicular alpha phase width, in the smallest dimension of the acicular alpha phase in the alpha colonies and in grain boundaries, of less than about 10 microns.