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...

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...

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...

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...

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...

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...