The magic behind the name “Martfrost”

17. dubna 2019

The Czechoslovak patent number 119692, published by the Czech metallurgical expert Jaroslav Jech, is the brains behind the mysterious name Martfrost. The essence of the patent is that the steel is heated to a quenching temperature of 1050-1010° C, then cooled in water to 250-300 ° C and immediately transferred to a nitrogen vapor bath.

This name "Martfrost” was inspired by the making process. "Mart" is the first part of the term "martensite", which is a very hard and solid supersaturated solution of carbon in iron, which is produced during quenching by rapid subcooling. Frost is an English term which means extreme cold.  

As a result of such quenching, the material has a hardness of 5 or more HRc units higher than during conventional quenching. And that's not all. It also strengthens its wear resistance. And when used with a knife, it not only has greater flexibility, hardness, and toughness but it also extends the durability of the blade.

Mikov used this hardening method from the 1970s to the 1990s. He applied it mainly to kitchen knives, hunting knives or UTON army specials. But since the existing stainless steel has approximately the same properties as the earlier Martfrost-hardened SONP Kladno steel, and this method has caused a great deal of environmental stress, Mikov abandoned this quenching method.  

However, freezing of steels after quenching as such has not disappeared in the abyss of time, some specialized centers of some companies still use it.