AUS-8 Stainless Steel

The single most important component of a good knife is the steel used to make it. A tough, versatile, damage-resistant steel can make or break a knife’s performance, as well as give them their high-quality standards. Stainless steel is a popular alloy type because of its unparalleled resistance to rust, as well as its convenient and stress-free ease of maintenance. The high chromium, Japanese-made AUS 8 stainless steel is an extremely hard, rust-resistant metal capable of acquiring a razor-sharp edge to satisfy any knife-user or lover. The exceptional balance of qualities offered by the steel sets AUS 8 aside from many other high-grade steels in its class, giving it countless reasons why you should look for it in a knife.

What is AUS 8 steel?

The Japanese-made AUS 8 steel is often considered an upper-range steel, comparable if not better than steels such as 440C, CM-154, and D2 steels. Given a proper heat treatment and hardened to the right level, which is usually around 58 to 59 HRC, it will perform satisfyingly and meet the standards of a true quality stainless steel. A well-rounded composition allows for this steel grade to reach high levels of hardness, toughness, wear and corrosion resistance, as well as edge retention.

Composition

Material %
Carbon .75
Chromium
  1. 5
Manganese .5
Molybdenum .3
Nickel .49
Silicon 1
Vanadium .26

This is a carefully balanced composition to ensure not just a great hardness, toughness, and harden-ability, but also the critically important qualities of wear, abrasion, and corrosion resistance that are vital in any good knife steel. Each of the above listed components in AUS 8 steel serve different and equally important purposes which, together, make it a quality steel superior to so many of the other steels in its class.

Carbon content in a steel will give it the hard-to-achieve quality of an increased edge retention, which cannot be attained through the use of other popular elements in stainless steels. Edge retention in a blade is so critical because it helps give the steel the attribute of keeping its edge for long periods of time.

In order to be classified as a stainless steel, a metal must have a chromium content of at least 10.5 percent- AUS 8 steel has a 14.5 percent chromium content. The benefits of the use of chromium include a significantly increased hardness and toughness, as well as a strong tensile strength (the ability to withstand maximum stress), wear, abrasion, rust and corrosion resistance. Chromium is one of the most beneficial components of a stainless steel due to these reasons, which add to its dependability as well as its ability to attain a razor sharp edge and last for very long periods of time.

In addition to adding to a steel’s tensile strength and corrosion resistance, manganese also contributes to AUS 8’s commendable grind-ability and harden-ability. Steels that are easy for welders to fashion make for better blades, and make them easier to sharpen when they get dull.

When added to steel and cast irons, molybdenum contributes to the steel’s weld-ability and corrosion and wear resistance. By increasing the steel’s lattice strain, the energy required to ruin the blade is augmented, making the steel significantly stronger and less susceptible to such damages. This ingredient is not commonly found in stainless steels, but is becoming more commonly used due to its low density and more cost-effective price, and has begun to replace the now less common ingredient of tungsten.

Another unique component of AUS 8 is nickel. When nickel is added to a stainless steel, the austenite structure of the iron is steadied. Although manganese does similar things to nickel, and nickel is generally more expensive, sufficient nickel content will weaken a steel’s corrosion resistance no matter how much manganese it has. Nickel also contributes to AUS 8’s laudable weld-ability, another reason why knife makers like it so much and prefer it over other high-grade steels.

Silicon is commonly found in stainless steels, offering an increased tensile strength to give those steels a greater maximum stress resistance.

Vanadium, a new and innovative additive to quality stainless steels, not only dramatically increases AUS 8’s tensile strength, but enhances what few other elements can offer by adding to the steel’s impact strength, a key component in ensuring a knife’s ruggedness and adding a pure dependability that will give you an unquestionable confidence in the steel’s ability to take abuse and come out unscathed. Such imperviousness to damages makes AUS 8 steel such a great candidate for use in even the most rugged survival/bushcraft knives. Vanadium is also reported to make steels easier to sharpen.

Despite the quality of AUS 8 steel, it should not be thought to be a premium grade steel, such as S35VN, ELMAX, and M390 steels. AUS 8 is a high-grade metal that is in the ranks of steels such as 440C and 8Cr13MoV grade steels. Therefore, knives with AUS 8 steel will typically be more in the 30 to 150 dollar range depending on factors included with the knife such as handle materials as well as overall workmanship, whereas knives with premium grade steels will fall more typically in the 150 to 500 range.

Why is AUS 8 steel so popular, who uses it, and for what purposes is it used?

Because of its superior composition, which allows for it to be so versatile and strong, AUS 8 has become popular among knife makers and knife companies, who use it to make many different types of blades.

Knife makers prefer this steel to others in its class for the reason that it can be “stamped,” as opposed to “forged.” Stamped knives are made from large sheets of stainless steel, able to be mass produced by a machine that stamps out the metal in the shape of a knife. Afterwards, the handle is added and the knife is sharpened and polished. This process makes knife-producing significantly more convenient and inexpensive than “forged” knives, which are created in a process where the raw metal is melted and shaped to the right size, then sharpened and polished- a longer and more expensive process.

The biggest improvement of the AUS series over the 400 Series is the addition of vanadium, which improves wear resistance and provides great toughness. This also reportedly makes the steel easier to sharpen.

AUS-6 Steel: AUS-6 Steel has .65 percent carbon and is generally considered a low-quality steel. It’s comparable to 420, but with better edge retention and less corrosion resistance.

AUS-8 Steel: This fairly popular steel has .75 percent carbon, which makes it fairly tough. It also has more vanadium than AUS-6, so it holds an edge better.

AUS-10 Steel: This has 1.1% carbon and is roughly comparable to 440C. It has more vanadium and less chromium than 440C, which makes it slightly tougher in comparison, but also a little less rust resistant.