440 martensitic stainless steel, 440 is not a single imagine something, 440 tail number A, B, C, D, E, F, each tail number of the ingredients are not the same, only suitable for the production of 440C, commonly used tool, 440C was originally developed for the production of stainless steel knife, knife after America carpenter for handmade knives, steel Village carbon is about 1%, the chromium content of about 13%~18%, heat hardness of about 58. Now the domestic production of 440C steel, but there is a clear gap between China and foreign countries, such as the United States, Japan foreign plate plate plate is best, followed by South Korea, once again is Taiwan plate, and finally the domestic foreign plate, sheet of chromium was significantly higher than the domestic, the smoothness of the plate than the domestic high, domestic plate with gray point.
Now many unscrupulous traders use the other 440 steel does not write the tail number when 440C steel material to mislead consumers, such as 440A with lower carbon content, soft material, rust slightly higher than 440C, the most for the production of diving knife, application is not so wide, the price of less than 440C, such as the cost of materials many low.
Buy a good knife is to have a certain knowledge, if it is to collect, it is necessary to study more, there is a good knife, there must be a good knife skills. Before buying, should see more, know, buy again.
