UNI-HARD® IR is a ternary eutectic mixture of chlorides in granular form. Its wide working range makes it a good general purpose neutral salt for the heat treatment of steel. UNI-HARD® IR is also very fluid, relatively stable, easy to wash and only slightly hygroscopic. Even without rectification, it has very little tendency to decarburize.

The wide working range of UNI-HARD® IR makes it suitable for many steel treating

applications. Besides heating for hardening, it is frequently used as a preheat and/or quench in high speed steel hardening, as a transformation bath in cycle annealing, for cycle annealing, and for tempering high alloy tool steels. UNI-HARD® IR can be used intermittently at temperatures from 1700°F – 1850°F; a carbon cover is recommended under these circumstances. This does not apply if the bath is used also as a high speed steel preheat.