The chromium refines the grain of the steel remarkably, owing to its tendency to prevent the development Of a crystalline structure. In the annealed state, every increase of chromium up to a content of per cent raises the tensile strength, while the elastic limit is gradually raised until a chromium content of per cent is reached. This latter remains constant until the chromium content has passed 9 per cent, but after this a rapid reduction takes place. In the hardened steels, both the tensile strength and the elastic limit increase until a chromium percentage of per cent has been reached, and beyond this point both gradually decline.