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Why is CPM 3V powder steel so strong?

Why is CPM 3V powder steel so strong?

17-05-2023
Composition CPM-3V Chemical %(Carbon 0.80; Chromium 7.50; Vanadium 2.75; Molybdenum 1.30)   CPM 3V (Crucible Industries in Syracuse, New York) - Introduced in 1997. CPM 3V is a tool steel made of metal powders with a unique chemical composition that provides the tool with a unique combination...
Characteristics of a gutting hunting  knife

Characteristics of a gutting hunting knife

24-04-2023
GUTTING KNIFE As the name suggests it is a tool that allows us to gut the hunted animal. Some hunters treat gutting as a necessity that concludesthe hunt, while others celebrate evisceration as the crowning glory of the hunt. Gutting itself is a tedious and sometimes  a very tiring task...
Knife sharpening - facts and myths

Knife sharpening - facts and myths

17-03-2023
Knife sharpening is a topic that always evokes a lot of emotions among knives enthusiasts. There are many myths around the subject of knife sharpening, which in fact introduce even more confusion and a helplessness among people starting their adventure with knives. Very often I have questions...
Characteristics of a hunting skinning knife

Characteristics of a hunting skinning knife

29-09-2021
Hunting trip into the forest often ends up with nothing more than admiring the nature and contemplating beautiful views. Sometimes however the hunter is granted good fortune by St.Hubert making him able to shoot some prey. In most cases hunted and then gutted animal goes to collection centre...
Knife for a hunter - which one to choose?

Knife for a hunter - which one to choose?

24-08-2021
Knife for a hunter - which one to choose? It can be said that the history of mankind is engraved with a knife. In the past, the possession and skillful use of primitive tools, slightly resembling modern knives, were decisive for survival. Over the centuries, with the development of technology,...
In what situations can a survival knife be very helpful? Check!

In what situations can a survival knife be very helpful? Check!

26-07-2021
The stereotypical thinking of many of us makes us believe that the survival knife and its possession clearly shifts our thinking into many weeks spent in the bush and the need to survive in it. Of course, in such conditions, it is definitely worth having the right quality equipment. However, it...
Hardening. Part four: Tempering.

Hardening. Part four: Tempering.

17-04-2020
                           After hardening, the workpiece is hard but brittle. Martensite, which appears in steel during hardening, has a very high stress in it, so that the knife is not brittle, it is necessary to remove some of this stress....
Hardening. Part Three: extinguishing.

Hardening. Part Three: extinguishing.

21-03-2020
How to choose a cooling medium? Again: expertise and experience or trial and error method. Based on the CTT (Continuous Cooling Transformation) diagram for a specific steel! https://en.wikipedia.org/wiki/Continuous_cooling_transformation                             Fig. 1 CCT...
Hardening. Part two: Why?

Hardening. Part two: Why?

12-01-2020
To what temperature I heat to, how long to keep the knife at this temperature: the manufacturer often presents it at a temperature scale but usually without the time of Austenitization! In what do I cool it in, how fast do I do it, are even harder questions. The manufacturer often provides...
Hardening. Part one: The basics.

Hardening. Part one: The basics.

13-11-2019
            Steel (iron alloy (Fe) with carbon (C)) without any special heat treatment, simply cooled after forging on the open air is soft. A knife made like this can bend in your hands. Before our ancestors had learned how to heat-treat steel, they forged it without any heat....
Resistance to cracking.  Part two: how can it be translated into knives and checked at home?

Resistance to cracking. Part two: how can it be translated into knives and checked at home?

20-04-2019
Another method to check the impact strength indirectly is the breaking-point test. Cutting the steel and hitting it with a hammer break the sample (e.g. knife) as in Izod's test. https://en.wikipedia.org/wiki/Izod_impact_strength_test When viewing a broken specimen under a magnifying glass, we...
Resistance to cracking. Part one: what is it?

Resistance to cracking. Part one: what is it?

31-03-2019
The mythical toughness  of steel for knives, everyone has heard about it, nobody has ever seen it. Impact strength is the material's resistance to cracking under sudden, rapid load / impact. This is the effort required to break a standardized sample, on a standard machine, under standardized...
Hardness. Part two: why it needs to be known and measured?

Hardness. Part two: why it needs to be known and measured?

09-03-2019
"But why do I need all of this information, how is it related to using knives?” The higher the hardness, the higher the resistance to the Cutting Edge (CT) deformation. Because it may seem that we use a low force on the material we are cutting, but that's not the case. The Cutting Edge is...
Hardness. Part one: hardness measurement.

Hardness. Part one: hardness measurement.

11-01-2019
Hardness. Part one: hardness measurement. Almost every material can be sharpened to cut. Many of us have cut our hands with a soft sheet of paper! You can sharpen the bottom of your bean can to shave your hair from your arm! But sharpness is one thing, and how long you can use it is another. How...
Rusting steel and stainless steel

Rusting steel and stainless steel

18-11-2018
Steel has many advantages, but its great disadvantage is the lack of corrosion resistance. Under the influence of Oxygen (O2) and Water (H2O), rust forms on the steel surface. The knife rusts in your pocket! Fig. 1 Rust on steel [2] The element that most strongly affects the corrosion...
Elements in steel. Part Three: Alloy elements.

Elements in steel. Part Three: Alloy elements.

18-09-2018
Alloy components are added to the steel to change its properties, however, they are not used to deoxidize the steel, they are too expensive to do so. Chromium (Cr) is the basic and most important alloy element in tool steels and structural steels used for making knives. It is so, because it is...
Elements in steel. Part two: steel additives.

Elements in steel. Part two: steel additives.

03-08-2018
In steel  besides Carbon (C) (and of course Iron (F)!), polluters, we can also observe the occurrence of  alloy elements which improve the properties of the steel. These are the reasons why alloy steels are better than a pure alloy of iron with carbon. The first group consists of admixtures...
Elements in steel. Part One

Elements in steel. Part One

12-07-2018
Banally, pollution plays a very important role right after coal. WHY? Because if there is too much of it, even adding the entire Mendeleyev table will not make the steel suitable for making knives out of it. Polluters in steel are Sulphur (S), Phosphorus (P), Hydrogen (H), Oxygen (O), Nitrogen...
What is steel?

What is steel?

05-07-2018
The material which is most commonly used in the manufacture of knives is steel. Below I present  the first part of a brief description of steel. Steel is an alloy of iron (Fe) with carbon (C) and other elements. Carbon is the main alloy element in steel. Iron + Carbon. That could easily be...