The high carbon content aids the hardenability to give considerable wear resistance. The chromium content adds to the strength and hardness characteristics of silver steel. As supplied, however, it is machineable owing to the annealing treatment given in production. Silver steel bar is spheroidised annealed for best machineability, the annealed hardness being in the region of 270 Brinell (Rockwell C 27). On hardening and tempering, a hardness up to 64 Rockwell C can be obtained. Being in the spheroidised condition, it offers maximum response to hardening and the chromium content ensures deep hardening. Silver steel bar is a popular tool room material used in a wide range of applications.
There is, of course, no silver in it, the term ‘silver steel’ is a traditional description. When the grade was fist developed in the early 1900s the addition of chromium (which at the time was becoming increasingly popular as an alloying element in steel) gave the steel a bright ‘silver’ like finish.
Silver steel can be used in numerous applications including screwdrivers, punches, shafts, axles, pinions, pins, die posts, instrument parts, model parts, taps and drills for mild steel, engravers ’tools, and fine cutters.