How to choose steel for a knife

The knife is one of the oldest tools possessed by humanity. Initially, they were created from various materials: stone, wood. But as soon as the world of metals became accessible to humans, the manufacturing process and requirements for this tool changed significantly.

Modern consumers have the following requirements for knives: strength, wear resistance, reliability, ergonomics, and sometimes non-standard design.

Depending on the intended purpose of the tool, the future steel for it is chosen. It's worth noting that there is no absolutely universal steel grade; each has both advantages and disadvantages.

What steel parameters to pay attention to

1. Hardness.

It is measured on the Rockwell scale, which has 11 gradations.

Ordinary mass-produced knives usually have a hardness of 54-58 HRC. And Damascus models can have a value of 59-64 HRC. It's worth noting that the higher the hardness index, the more brittle the knife, but it retains its sharpness longer. Ordinary kitchen knives have a hardness from 30 to 50 units.

2. Strength.

The durability of the tool depends on this parameter; there is no scale to evaluate this indicator. It characterizes the metal's resistance to brittleness and crack formation, as well as how much the blade can bend without destructive deformation. The higher the strength, the more resistant the metal. But here, as in the case of hardness, the highest strength has the greatest brittleness, so ideally, a balance must be maintained.

3. Corrosion resistance.

Any steel is prone to corrosion to some extent, but manufacturers strive to make the blade resistant to rust formation even in case of constant contact with acidic, humid, or salty environments. The corrosion problem is solved by introducing various additives. For example, chromium, molybdenum, titanium, nickel.

4. Wear resistance.

This parameter characterizes the metal's resistance to adhesive or abrasive destruction during normal use. It is directly affected by the chemical composition of the steel and its strength. The higher the wear resistance, the longer the knife's service life.

5. Edge retention.

This parameter is quite subjective and characterizes the duration of blade sharpness retention under conditions of constant use. Alloyed tool steel can maintain cutting qualities for a long time.

Note that the resistance of the cutting edge to dulling is affected by the sharpening angle, which is different for each tool. For chopping blades, it's 35° and above, and machetes need to be sharpened with a fully curved cutting edge.

6. Chemical composition and properties of additives

It's worth noting that all characteristics of knife materials are influenced by the chemical composition of the material. For example, the optimal carbon content should be 1%. Various additives neutralize excess carbon and make the metal stronger. If this indicator is above 1%, the metal will be too brittle.

Stainless steel is made by adding chromium, introduced in an amount of 13%. Such a blade will be resistant to corrosion and will not dull for a long time.

Nickel is added to increase corrosion resistance and hardness. Molybdenum is added to increase resistance to aggressive environments. Tungsten and vanadium improve the cutting qualities of knives and blades and their wear resistance. Silicon and manganese are added to increase strength.

Which steel grades to choose

Low-carbon steel and stainless steel

It's worth noting that kitchen knives should not be made from cheap low-carbon stainless steel. Products made from such material can be distinguished by sound: if you tap on the blade, it will produce a dull sound rather than a ringing one.

Among the relatively affordable steel grades is grade 1.4110, a martensitic stainless steel with a hardness of 54-58 HRC. Also included here are steels 1.8159 (50XGA), 1.3505 (SHX15), and 1.1750 (65G).

Grade 1.4021 (420).

As a material, it predominates in the low and medium-priced class of knives. It has high corrosion resistance. Resistant to cracking and chipping. It hardens to 54-57 HRC.

Steel 1.4125 (440A), 1.4112 (440B), 1.4110 (440C).

Varieties of this steel differ in carbon content, and consequently, the strength of the cutting edge. A very popular material in the European and American markets. Well suited for knives made by hand by masters.

Bulat is a cast, high-hardness, elastic steel with a peculiar structure that has a characteristic surface pattern formed during the etching process, as well as processing. A product made of bulat holds its edge well, and the most elite knife brands are made from stainless bulat.

Damascus ("lacy") is one of the optimal for knives made by forging. The less prominent the pattern, the denser the metal. But such knives have a significant drawback - they need to be carefully maintained because they are prone to corrosion.

Powder steels

These are the highest quality tool steels. The molten metal is processed into powder, and necessary additives are added to it. Then it is dispersed to a plastic state in an inert gas. Then it is compressed under high pressure and temperature in special forms and baked. It has a fine-grained structure that is easily polished. They are well-suited for hardening, wear-resistant, and maintain the necessary viscosity.

Which steel grade will be better

It's impossible to answer this question definitively. For example, carbon steels sharpen well but are easily susceptible to corrosion. Powder steels have excellent cutting properties but are difficult to sharpen.

By price segments, three categories can be distinguished: premium class, medium-priced, and low-priced.

Premium class

M390, ZDP-189, VG-10, 154CM. These steels are suitable for surgical instruments, as well as for making expensive and custom segment knives. They have high hardness, good sharpening, are wear-resistant and impact-resistant.

Middle class

These steels are characterized by sufficient strength, quick sharpening, long edge retention, but are more prone to corrosion. These include: 1.4034 (420HC), AUS-8, 8Cr13MoV, X12MF, 9XC.

Lower class

Such steels are not suitable for professional lines of cutting tools. They rust very quickly and bend strongly: 1.1750 (65G), 1.4125 (440A), 1.4021 (420), 1.4037 (65X13).

For ordinary kitchen knives, 1.4037 (65X13) and 1.4034 (40X12) steel are often used. They don't rust as much, sharpen well, but due to their softness, they quickly become dull and bend.

For a gift item, it's better to use premium-class material.

You can buy various steels for knives at the metal bases of UTMK company in Kyiv, Boryspil, Dnipro, Odesa. Delivery of rolled metal batches from one ton is carried out to any settlement in Ukraine or Europe, including Romania, Hungary, Croatia, France. Polish buyers can make a purchase at the UTMK base in Warsaw, Lodz, Krakow, Poznan. We deliver to Żary, Głogów, Legnica, Opole. The minimum order for delivery is one ton. Wholesale buyers are given a discount. Contact us, our managers will help you choose the optimal option.