Steel Element Information
Carbon (C):
1. Increases edge retention and raises tensile strength
2.Increases hardness and improves resistance to wear abrasion.
Chromium (Cr)
1.Increases hardness, tensile strength and toughness
2.Provides resistance to wear and corrosion
Cobalt(Co)
1. Increases strength and hardness and permits quenching in higher temperatures
2. Intensifies the individual effects of other elements in more complex steels.
Copper( Cu)
1. Increases corrosion resistance
Manganese (MN)
1. Increases harden ability, wear resistance and tensile strength
2. De-oxidizes and de-gasifies to remove oxygen from molten metal
3. In larger quantities, increases hardness and brittleness
Molybdenum (Mo)
1. Increases strength, hardness, harden-ability, and toughness
2. Improves machinability and resistance to corrosion.
Nickel (Ni)
1. Adds strength and toughness
Phosphorous (P)
1. Improves strength, machinability and hardness
2. Creates brittleness in high concentrations
Silicon (Si)
1. Increases strength
2. De-oxidizes and de-gastifies to remove oxygen from molten metal.
Sulphur(S)
1. Improves machinability when used in minute quantities
Tungsten (W)
1. Adds strength, toughness and improves harden-ability
Vanadium (V)
1. Increases strength, wear resistance and increases toughness.
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PERFORMANCE
Good looks are important, in knives as much as in life! Perfect fits, clean lines, precise grinds and beautiful polishes all add value and satisfaction when you buy a knife. Often, the true beauty of a knife only becomes apparent when the knife is used!At Cold Steel. we believe that all of our knives must perform. We insist all of our knives deliver extraordinary performance for their asking price- " they must deliver their money's worth".
In order to achieve this goal, we are vitally interested in all the elements that are critical to performance. When it comes to the blade, these include profile, thickness blade geometry, steel and heat treatment. Every one of these factors is studied in minute detail to arrive at the optimum combination for a specific use. If the knife is a folder, we concentrate on the locking mechanism to ensure the strongest. safest construction. For handles, we strive to develop the perfect mix of materials and ergonomics to offer the most comfortable secure grip available. Above all, we TEST what we make! Rigorous testing is the only way to ensure we get the level of performance we demand.
VG-1
When considering a new material for a performance upgrade for the Cold Steel Tanto, we tested seven different grades of steel including Shiro 2, V-SP-2, 10A,440C, VG-10, ATS 34, and VG-1. Physical testing for sharpness, edge retention point strength, chock, and ultimate blade strength showed that while many of the steels had increased the greatest performance in one or two testing categories, only one, VG-1, showed the greatest performance increases in the most critical categories. With an outstanding ability to retain an edge and proven strength in point and blade tests, VG-1, will provide Cold Steel customers with superior performance previously unavailable in a stainless steel blade.
4116 KRUPP Stainless
4116 is a fine grained, stainless steel made by Thyssenkrupp in Germany and is used for hygienic applications(medical devices and the pharmaceutical industry) and food processing which make it a superb material for kitchen cutlery. The balance of carbon and chromium content give it a high degree of corrosion resistance and also impressive physical characteristics of strength and edge holding. Edge retention in actual cutting tests exceeded blades made of the 420 and 440 series of stainless steels. other alloying elements contribute to grain refinement which increase blade strength and edge toughness and also allow for a finer, sharper edge.
AUS stainless
The words "stainless steel" are misleading, because, in fact, all steel will stain or show discoloration if left in adverse conditions for a sufficient time. Steel is made " stainless" by adding Chromium and reducing its Carbon content during the smelting process. There is a serious performance trade-off with stainless steel. As the Chromium increases and the Carbon decreases, the steel becomes more "stainless". But, it also becomes more and more difficult to sharpen, and the edge-holding potential is seriously impaired. This is usually why most stainless knives are rarely razor-sharp and quickly lose what little edge they have.
In contrast, at Cold Steel we use AUS 8A stainless, a high Carbon, low Chromium steel that has proven itself to be the ultimate compromise between toughness and strength, edge holding, and resistance to corrosion.
Aus 6A is a medium high Carbon stainless which is tougher than AT-34, 440C, ATS-55, etc, but still holds a good edge. This means it is particularly well suited for heavier, longer blades that are subjected to a lot of stress while chopping and hacking.
SAN MAI III
San mai means " three layers". It's the term given to the traditional laminated blades used by the Japanese for swords and daggers.Laminated construction is important because it allows different grades of steel to be combined in a single blade. A simple way to think of this type of construction is to imagine a sandwich: The meat center is hard, high carbon steel and the pieces of bread on either side are the lower-carbon, tough side panels. The edge of the blade should be hard to maximize edge holding ability, but if the entire blade was hard it could be damaged during the rigors of battle. For ultimate toughness the body of the blade must be able to withstand impact and lateral stresses. Toughness is generally associated with “softness” and “flexibility” in steel, so that, surprisingly, if a blade is made “tough” the edge won’t be hard enough to offer superior edge holding. San Mai III provides a blade with hard (high carbon steel) in the middle for a keen, long lasting edge and tougher (lower carbon) steel along the sides for flexibility.
1055 Carbon
1055 steel is right on the border between a medium and a high carbon steel, with a carbon content between 0.50%-0.60% and with manganese between 0.60-0.90% as the only other component. The carbon content and lean alloy make this a shallow hardening steel with a quenched hardness between Rc 60-64 depending on exact carbon content. These combination of factors make this one of the toughest steels available because when quenched, it produces a near saturated lathe martensite with no excess carbides, avoiding the brittleness of higher carbon materials. This steel is particularly suited to applications where strength and impact resistance is valued above all other considerations and will produce blades of almost legendary toughness.
SK-5 High CarbonSK-5 is the Japanese equivalent of American 1080, a high carbon steel with carbon between 0.75-0.85% and 0.6-0.90% manganese. As quenched it has a hardness near Rc 65 and produces a mixture of carbon rich martensite with some small un-dissolved carbides. The excess carbide increases abrasion resistance and allows the steel to achieve an ideal balance of very good blade toughness with superior edge holding ability. Due to these characteristics, this grade of steel has been used traditionally for making variety of hand tools, including, chisels and wood cutting saws, and has stood the test of time and use over many years in many countries.
65Mn is formulated to provide good wear resistance and hardness. The medium-high carbon content makes for a high degree of toughness and resilience, while the manganese, in addition to improving these properties, improves the hot-working characteristics of the steel, making it an excellent candidate for forged sword blades.
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HOW TO CHOOSE A KNIFE
SOURCE: Bill Bernhardt, May 25, 2014, HOW TO CHOOSE A KNIFE: MIND YOUR NEEDS
I also mentioned that for knives regularly subject to impact such as camp knives, survival knives, military knives and machetes, you need to choose a tough steel rather than a hard steel. For high quality hunting knives, you need to choose a hard steel rather than a tough steel.
Well, if toughness, keenness of edge, and/or ease of resharpening are of paramount importance to you, then choose a knife made from a high carbon tool steel such as 1095, 5160, O1, or A2. The high carbon blade steels tend to be softer but has a finer grain structure with better edge performance and toughness than stainless steels.But, which blade steel do you choose for your particular purpose?
On the other hand, if edge holding ability and corrosion resistance are most important to you, then choose a stainless blade steel such as CPM S30V, VG-10, 154CM, ATS34, or 440C.
Keep in mind stainless steels tend to have poorer edge performance and be less tough than high carbon steels.
Furthermore, for large, high-impact, knives such as Parangs, Eneps, and Kukris, a non-stainless steel such as 1055 or 65Mn is best. But for military or survival knives, one of the harder, high-carbon, tool steels such as 1095 mentioned above is best.
If you’re looking for superior edge holding ability and corrosion resistance, choose a premium stainless blade steel such S30V or VG-10. For slightly lower performance choose D2, 154CM, or ATS34 and, for large stainless steel knives such as Bowies, choose 440C.
Another factor that you’ll want to consider when choosing a blade steel is the Rockwell Hardness (Rc) of the finished blade. Hardness and toughness in a knife blade are inversely proportional.
Therefore, although the perfect blade steel would be one that is both hard and tough, no one has yet managed to formulate such an alloy. Softer blade steels (Rc 52-54) are tougher than hard blade steels (Rc 58-62) but they do not hold an edge as well.
Hard blade steels hold an edge better but are more prone to chip or break because they are more brittle.
Last, you will want to note the elemental composition of each blade steel. For instance, Carbon converts iron into steel and makes it harder whereas, Chromium increases the wear and corrosion resistance.
Molybdenum increases hardness, abrasion resistance, and corrosion resistance and Manganese is an inexpensive means of refining the grain structure, which increases toughness and hardness. Tungsten and Vanadium are better, but more expensive, ways of achieving the same goal.
So, when choosing a blade steel, it is very important that you first identify your needs and then chose an appropriate blade steel accordingly in order to obtain the best performance for your particular purpose.
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