New site SR101 description

[Blade Runner 7]

Did anyone else read it? It says SR101 is differentially hardened. The Yard says that too. I thought they didn't do that anymore.

 

[azwelke]

I can see a hamon on my stripped 1311
I thought some were and some weren't?

 

[leatherman]

Apparently some are and some not. The R9 from what I remember is through hardened, as is most all the R line. I think?

 

[shrapnelwound]

I saw that description and was wondering about it too. To my knowledge they are not diff heat treated. Must be a mistake.

 

[magoo48]

The description says: : "multi-step tempering protocol". This is quite common in annealing steel. Multi tempered and multi quenched is most likely what they mean, IMHO. Just my 2 cents.....

 

[shrapnelwound]

This is the quote I was referring to:

"SR-101 Steel is the combination of an extremely fine-grained tool steel and a proprietary multi-step tempering protocol. This process includes the incorporation of a deep cryogenic treatment for grain refinement with the added benefits of differential tempering which add greatly to the overall toughness and strength of what will most certainly prove to be your favorite blade."

"Differential tempering".........sounds like diff heat treat to me and if not, this is confusing for people who don't know as much as some of us do about these knives.

 

[elof_alv]

DHT is not the same as differential tempering.

Tempering occurs after HT, process that stabilizes structure and relives stress in the steel and reduces brittleness.

 

[Nullity]

DHT is not the same as differential tempering.

Tempering occurs after HT, process that stabilizes structure and relives stress in the steel and reduces brittleness.

Whether or not it is differential hardening or differential tempering, the end result is a knife with a softer/tougher spine and a harder cutting edge, right?

 

[shrapnelwound]

DHT is not the same as differential tempering.

Tempering occurs after HT, process that stabilizes structure and relives stress in the steel and reduces brittleness.

Ok, thanks for the clarification.

 

[elof_alv]

Whether or not it is differential hardening or differential tempering, the end result is a knife with a softer/tougher spine and a harder cutting edge, right?

There are different ways of tempering, and different steels require different temps and cycles.

I have seen a roughly ground knife being heat treated and then broken with just a heave of an average built man. Knife/blank was in a vise, he just tugged at it, throwing his body into it.
Afterwards the broken knife got back into the forge and got a basic tempering cycle and it was able to support his weight without deformation or breaking.

Differential tempering might mean multiple tempering cycles at different temps.
It still produces a through hardened blade, but the grain/structure of steel is much finer and more 'elastic' making it more resistant to breaking and wear.
Imagine that steel is like a bread and has empty spaces inside - bubbles, and concentration of denser material like firmly packed dough around the bubbles. The tempering (bringing the steel to certain temp for a certain time) disperses the bubbles and loosens up the packed material until the bubbles disappear completely and the structure of steel is mostly even.

That's why the powdered steels were invented, to give a uniform structure before heat treating, so after the whole process is done the blade is a lot more uniform.