To the Inheritors of Samurai History
About Us
威風 Ifu – The Authentic Katana Lab-
We are Authentic Katana geeks who love science and history.
We have loved studying since we were young and immersed ourselves in research activities at the University of Tokyo and Kyoto University, but when we encountered Authentic Katana, we were completely fascinated by them.
Now we spend our days exploring the mysteries of Authentic Katana.
We will carefully select valuable Authentic Katana from the viewpoint of both science and historical romance.
We are pursuing attractive Authentic Katana to deliver to fellow Authentic Katana enthusiasts around the world.
The mystery of Authentic Katana Sharpness
Here we would like to introduce some of the mysteries of Authentic Katana.
The thing that everyone is curious about the sharpness of Authentic Katana! Authentic Katana are said to be the sharpest blades in the world, but how do they achieve such excellent sharpness?
Cutting something may seem a simple phenomenon, but it is extremely difficult to evaluate it. There are many ways to evaluate it, it also depends on the cutting speed, and the user’s sense also comes into play.
We will approach the subjective quality of sharpness, which tends to be a personal matter, from as scientific a perspective as possible.
There are two ways to cut with a blade: pushing and pulling, but I’m sure everyone has experienced that pulling cuts produce a better sharpness.
The reason why the blade cuts better when it is pulled is because of the tensile stress. The following figure shows a model of “pulling and cutting”.
First, the blade is pressed against the blade, which generates (1) Cutting force. Then, by sliding the blade forward, (2) frictional force is generated at the contact point with the blade. These two stresses generate an extremely large (3) separation force in the direction perpendicular to the cutting surface. When this tensile stress exceeds the tensile strength of the material, the material is separated.
In other words, cutting is not a phenomenon in which the material is forced to separate by a sharp blade, but rather a phenomenon in which “the material willingly separates itself” because a separation force greater than the tensile strength is generated inside the material.
As we have seen, the coefficient of friction is actually essentially more important for sharpness than the sharpness of the blade. Although it may seem from these principles that the sharpness of the blade has nothing to do with sharpness, of course, the sharper the blade is, the better the sharpness will feel. This is because the sharper the blade, the smaller the deformation zone, and thus the less force is required to cut.
Why Katana is truly precious
We only deal in authentic antique Katana produced from the Muromachi to Edo periods(1336-1867).
Naturally, the total quantity of swords is fixed, as no new swords are ever produced.
The export of swords from Japan to the rest of the world is increasing year by year, which means that the number of Japanese swords in Japan will decrease and they will become more and more difficult to find.
As swords become more and more valuable, we cannot sell them to just anyone.
Therefore, we sell to Japanese professionals, but not to any Japanese individuals. We sell only to overseas collectors.
This is because we want to respond to overseas collectors who are interested in our home country, Japan, in this wide world.
Why choose us?
Katana geek selection
We are Authentic Katana geeks who love science and history. For example, while we think about why Authentic Katana are so beautiful and strong from a metallurgical point of view, we also wonder how these Authentic Katana have influenced the history of Japan. We will recommend Authentic Katana that we feel confident are worthy.
Continuing research
We have been immersed in our studies since our school days and have conducted research activities at the University of Tokyo and Kyoto University. After encountering Authentic Katana, we have become completely fascinated with it, and we spend our days exploring the mysteries of Authentic Katana.
0% return rate
We only deal in attractive products. We are sincere in dealing with our customers. We also provide our customers with as much information as possible about the condition of the item in advance.
As a result, we have never had a customer request a return.
Customer Reviews
Customer Satisfaction
Non-return rate
Positive Reviews
FAQ
We only deal in Japanese swords of historical value that have been produced more than 100 years ago.
We only deal in Japanese swords of historical value that have been produced more than 100 years ago.
We only deal in Japanese swords of historical value that have been produced more than 100 years ago.
Our Japanese swords are authentic Japanese swords produced by traditional methods, so they are extremely sharp. Please handle with care to avoid injury.