I have some laser-cut filing templates, about the size of a business card, made from 3mm-thick 1095 carbon steel. These parts will be used to guide a round metal file when filing odd shaped holes in aluminum. They will be clamped onto 13mm-thick aluminum and used as a filing "stencil". Thus the parts are not structural, but they need to withstand light pressure from a file without themselves being substantially filed. Aluminum is very soft, and I believe that with only light filing pressure, if the steel stencil pieces are hardened properly, the file will "skate" over them so they last essentially forever.
This is the process I was given by the laser cutter for hardening the 1095 steel:
- Coat pieces with boric acid to prevent scale and decarburation. Heat the pieces up until they don't attract a magnet
- Immediately quench the pieces into light oil, brine, or water (how do I choose?)
- Immediately temper at 200C for 1 hour and allow to natuarally cool
From what I can tell, the last step is designed to prevent the parts from being excessively brittle, but may slightly reduce surface hardness. Since the parts aren't structural anyway, and I am trying to achieve maximum hardness, is there any benefit to performing the tempering step?