Choosing the best pocket knife is difficult enough when you are a knife enthusiast, but for a novice there are so many things to learn. One question that I find most beginners (and some pros) ask me is which steel is the best for the blade of a knife? It is a really good question because a blade is only as good as the steel it is made from. The first thing I tell people who ask this question is that not all steel is created equal. In fact, there is a huge difference between a premium steel and a budget steel. I want to share a little bit about these differences and help you choose a steel that will last you long into the future.
Steel is basically a mixture (alloy) of iron and carbon. Steel makers can add other metals to the alloy to improve/change the properties of the steel. For example, chromium is commonly added to create stainless steel and improve corrosion resistance. The most common additions to the alloy in knife blades include Vanadium, Tungsten, Manganese, Nickel, Cobalt and Molybdenum. The amount of carbon in the alloy is very important because high carbon steel is much harder than low carbon steel and this is an important factor in a knife blade. The following are the characteristics that each additive brings to the steel.
Vanadium – improves wear resistance, increases durability, allows the blade to be sharpened into a very sharp edge.
Tungsten – Similar to the improvements of vanadium
Manganese – Improves toughness and the hardening of the steel.
Nickel – Increases strength and toughness.
Cobalt – Increases strength and hardness
Molybdenum – combines with chromium to form bonds that improve abrasion and corrosion resistance of a blade.
The characteristics of the steel can also be changed by the way the blade is rolled and heated in the finishing process. Some blade manufacturers also choose to coat the blade to further improve the finish.
Important blade properties
Strength – The strength of the blade when it is faced with stress and strong forces.
Toughness – The toughness relates to the ability of a blade to resist damage such as cracking and chipping during use and how well it flexes without breaking.
Hardness – Similar to strength and relates to the ability of the blade to resist permanent deformity.
Corrosion resistance – The ability of a blade to resist corrosive forces, such as rust, caused by external factors (salt water for example). There is some trade off between corrosion resistance and blade edge performance.
Edge Retention – How long the blade will remain sharp before re-sharpening is needed.
It might seem simple to add off of these properties and create the perfect knife blade steel, but there is actually a fine balance between these properties. For example, a blade that has high strength or harness with have reduced toughness. Choosing the best steel for your knife really comes down to what you are going to be using the knife for. For example, you may need a high corrosion resistant steel if you are using a knife for salt water fishing.
The most common types of knife steel
First Class Steel
BG-42 – A premium steel which is known for a superior ability to hold an edge. It is highly resistant to wear and tear, but can be difficult to sharpen.
S30V – Many consider this to be the best knife blade steel available. It has a great balance between hardness and toughness. It resists corrosion and rust while remaining great edge retention. This steel is only ever found on high end knives.
D2 – This is a very hard steel and it retains a great edge. Of course, the trade off is that this steel is harder to sharpen. D2 is classified as a semi stainless steel, but it remains very resistant to corrosion.
154CM – An American made steel that is known for its toughness and ability to hold an edge. It is also suitably resistant to corrosion.
ATS-34 – The Japanese equivalent of the 154CM. It is very popular with knife manufacturers at the moment. The lower corrosion resistance of this steel is the only glaring downside.
VG-10 – Very similar to the 154CM and ATS-34, but with added vanadium. This means that it is often considered to be of a slightly higher quality.
AUS-8 – A Japanese made steel that is highly resistant to rust/corrosion. It also has great toughness, but does not hold an edge as well as some of the higher quality steels.
440C – This is the most common steel used in lower end/mass produced knives because it is affordable as well as being a good all round steel. It is highly corrosion resistant.
420J – This steel is used in budget pocket knives and it works well for most general applications. It is a tough steel, but is susceptible to wear and tear. This steel quickly loses its edge and needs to be re-sharpened often.
It is important to research the steel used in your pocket knife, but try not to become obsessed finding the perfect steel. All modern knives use decent quality materials and will perform well enough for most tasks. Although the blade is an important part of the knife, there are many other factors that you should also consider when choosing a knife.