I'd be inclined to recommend a good solid state physics book, like Chaikin & Lubensky for scattering, and there are other topics that are probably not so bad for a materials scientist to have under their belt, presented in the kind of extreme-simplified "spherical cow" approach that physicists cherish.
But if you're looking specifically for something the Materials Science majors typically read, then yeah, Callister is pretty popular.
It's also worth mentioning that for individual topics, there are usually reviews and pedagogical papers that cover the material better than any textbook. For neutron scattering, my first exposure was a short review called "Neutron Scattering - A Primer". Now I see that the entire issue of the magazine it was in was dedicated to neutrons and is free online.
So I hope this helps!