Samurai Sword Store

Many quality forges specialize in the making of blade body. As such they pay especially close attention to the steel used and the temper/hardening process. They use several different types of steel which are not widely used by other sword makers. Some may purchase and use new billets from steel manufacturers (as opposed to use of recycled junk steel or building girders.)

Furthermore, quality forges very much focus on the heat-treatment methods used to extract the most optimal quality within the steel itself.

The Steel Guide:

The following is a simple guide to help you in selecting a blade that is right for your use. It will explain what each of the steels are and what our stance on it is below the chart: (TH denotes Through Hardened, DH denotes Differentially Hardened, LAM denotes Laminated).

Steel Types:

The system for identification of steel types in the US is based on the numbers assigned (i.e. 1060) (AISI). What these numbers represent are the major alloying agents and the carbon contents contained in the particular steel. The first two digit will refer to the major alloying agent and its percentage. The second two digits represents the carbon content in 1/100 of a percent.

The 10XX series represents carbon steels with no major alloying agent.... so 1045 means that the steel is a plain carbon steel with a 0.45% carbon content and the 1060 will have 0.6% carbon content. Traditional Japanese blades generally has a carbon content between 0.4% to 0.8%.

However, carbon content by itself really means nothing at all if a blade is not heat treated properly. Carbon add its value during the forging process by combining with iron to form a crystalline structure called martensite, which will harden the steel. During the forging process, carbon loss and carbon migration may occur if the temperature and timing is not controlled correctly. The tempering of a blade does not gurantee formation of the martensitic structure, but rather the hardening process. Carbon contents merely holds the "potential" or promise of a potentially specific metal quality, but not a gurantee.

With that said, quality forges are very proud of their heat treatment process as it is extrememly efficient in extracting the optimum quality out of each steel.

As for the other two digits, there are a variety of agents available and used on swords. For example, a 5XXX denotes Chromium and a 9XXX denotes Silicon. Each agent changes the properties of the steel differently. Chromium will increase the hardness of a steel and will also prevent staining or corrosion. (Stainless steel are made with the addition of 10.5% ~ 15% + chromium -- which is why it is so brittle and unsuitable for use in katanas).

In the case of Cheness, they used Silicon, which increases the resistance to metal fatigue, in our spring steel blades. This give the blade a better ability to resist being bent (set) by giving it a more "rubber like" property. The hardness of the blade is not changed, but only the resilency is increased.

BE WEARY OF SELLERS MAKING UNSUBSTANTIATED CLAIMS REGARDING THE QUALITY OF THEIR STEEL. It is very common on internet auction sites that the seller will claim a certain quality of steel above what is true. This is because it is very difficult for the general public to see a difference in the steels visually.... a 1045, 1060, 9260, 5290, 1095 can all be made to look identical.... However, the difference will become apparent after prolonged use of the swords. Also, while it may be true that a certain blade is made of a specific steel... (ie. 1060, it may not have gone through the correct heat treatment process to have the steel harden properly).

A rule of thumb is pricing. When a sword is sold for very cheap, it generally means that the steel used is very soft.

The bulk of the price/cost of a sword is in its shaping/polishing/sharpening process.... The harder the steel is, the more difficult it is to polish by hand. When a sword is priced very low, it is generally because the steel used is very easy to polish.... thus, very soft.. (which means that the steel used is either low carbon or not tempered correctly).

A well tempered, high carbon steel will cost more to make because of the added time it takes to polish.

An example of the price/time factor is the spring steel blade. The steel used in the spring steel blades are so resilent that it is very difficult for the shapers to adjust any forging mistakes out of the blade. (curves, kinks, warps)... As a result, the blade needs to come out of the forging process without mistakes.... otherwise, it becomes unusable and is scrapped or has to go back to the forge. It is because of this high forging tolerance requirement that adds time to the forging/re-forging process that makes this blade more expensive (not just based on the raw material cost).

Regarding Sharpness:

A sword can be "too sharp". What this means is that the cutting edge of a blade can be made too thin so that its relative durability is significantly reduced after frequent cutting. As you can imagine, the cutting edge of a sharpened blade from a primary (only) bevel has very little lateral support due to the small entry angle. For every type of steel, there is a minimum angle... beyond which, the steel will easily crumple (roll) from cutting (especially evident from harder targets). A katana that is "too sharp" will cut light targets easily, but roll its edge after only a few cuts.

To address this, the traditional Japanese swords generally has some body built into it's profile ("niku" or "meat" of the blade). This body is sometimes referred to as the "appleseed" or "clam" shape. This shape increases the durability of the blade, but slightly reduces the sharpness or cutting ability of the blade from the increased angle of entry.

Since many quality swords are mostly intended for use within a dojo setting, we do leave alittle "meat" on the blade. Some forges only sharpen their swords to a degree sufficient for cutting of goza mats or tatami omote. What this means is that although it may feel less "sharp" than other swords available (especially during the "paper test" or on very light targets), it is more than sufficient for mat cutting exercises. The results of this is that the cutting edge of our blade will more durable after prolonged cutting of heavier targets over time than otherwise.

AISI/American 1050/10xx - A good choice! While not identical to medieval Japanese steel, this plain carbon steel is the closest we have today. AISI 10xx steel contains iron, manganese and carbon, thus differing slightly from traditional steel. AISI 1065 maybe closer in carbon content to Traditional than 1050, but 1050 is tougher steel, and compensates somewhat for the lack of silicon in the steel (silicon improves strength and flexibilty). The xx in 10xx indicates the percentage of carbon, where 1050 has .50% carbon, and 1070 has .70% carbon, etc. The higher the carbon content, the harder the steel. The lower the carbon content, the more tough the steel is. Too hard, and the blade can shatter upon impact. Too soft, and it can easily be cut through. Many ask, "Which is the best for swords?" However, it's all in the heat-treating. But generally, you want a low-alloy steel for your sword. The biggest difference between 10xx and traditional Japanese steel tamahagane is the presence of manganese in 10xx but also the lack of silicon.

High carbon steel - High carbon spring steel.
They may use words like "Spring Steel" or "Live Steel" in their sales pitch. Spring Steel is a term that refers to any member of a group of steels that various types of springs are usually made out of (e.g, car springs are commonly made of 5160, but they can also be 1065). "Live Steel" is another euphemism for "plain carbon steel" (i.e., it can refer to any of 1050, 1065, 5160, CK55 or any plain carbon or low alloy steel) used by one mail-order/web company. Because these are not stainless, swords made of these materials do require oiling to prevent rusting. You may want to keep Iberia swords outside of their scabbards to avoid moisture damage and corrosion from chemicals used to treat the leather. Their high carbon spring steel is from the Philippines and comes from automobile springs (typically 5160), and can flex somewhat and return true. The high carbon steel used in Indian swords is similar to 1065. But, watch out! Even though many Indian, Filipino and Malaysian companies use superior steel, they put it through very poor heat-treating, which results in an inferior blade! In terms of "bang for the buck" you're getting an okay sword, but I wouldn't bet my life on an Indian, Filipino or Malaysian blade due to low-quality tempering.

Damascus steel is interesting. The original Damascus was a crucible steel with an extremely high carbon content. When forged into a blade, the carbides in the steel formed into a pattern that was visible on the surface of the steel. This material is also called "Wootz" or "Bulat". What most people think of today when they hear the word "Damascus" is actually pattern-welded damascus. Now this steel is composed of many layers of high and low carbon steel, and when etched, the high and low carbon steels are attacked at different rates by the acid, resulting in a visible pattern. Pattern-welded steels have existed since man began working with iron and steel (the Vikings made many pattern welded blades, however the technique fell into disuse until after the Crusades, when the smiths attempted to re-create the appearance of Wootz blades brought back by the knights by pattern welding steels).