Just read Carter's newsletter...
It included a very interesting history of Blue and White Steel... I think everyone should read it, especially people who are still confused with the differences between the two steels...
I don't know if it's okay that I post it, but I think this is very good info and everyone should have a read... here it is...
From The Murray Carter Newsletter...
Many connoisseurs of fine Japanese cutlery are well acquainted with the terms white steel and blue steel. These terms refer to the Hitachi high carbon steel that is smelted exclusively for use in laminating to mild steel for the production of the world's finest blades ever known to man. When skillfully joined to the mild steel laminate through a process known as forge-welding, the result is a blade with superior metallurgy that will sharpen easily, take a scary sharp edge and hold that edge longer than others.
After the end of World War II the leadership at Hitachi Metals decided to create a blade steel that was better than the best steel available at that time, Swedish Steel. As Japan had a long tradition of samurai swordmaking, it was decided that the new steel be modeled after the best blades ever forged. Several swords were analyzed for carbon content and alloy composition. What was discovered was that the swords averaged a little over 0.7% carbon and amazingly, they were very free from alloys and contaminants such as phosphorus and sulfur. This was the result from careful forge-welding and forging multiple times in a very clean fire made from pine charcoal.
Unlike swords which must be designed to withstand a lot of impact, the new steel was primarily going to be used in shorter lengths and used for daily cutting tasks which were not as abusive in nature. With edge holding capability in mind, a higher carbon content was considered, between 1.2% and 1.4% to be exact. To get the other advantageous qualities of the swords in their new steel, namely superior cutting performance and ease of sharpening via excellent carbide dispersion within the steel matrix, special attention was paid to ensure minimal impurities (phosphorus and sulfur) were present in each new batch of smelted steel.
The result of the engineer's efforts at Hitachi was a brilliant success. The old-school bladesmiths were quick to adapt to the new steel and apply their long years of forging experience to bring out the best potential the white steel had to offer. White steel #1(1.4% C) and White steel #2 (1.2% C) soon replaced Swedish steel as the premium choice for forge welding to make the finest blades on the Japanese domestic market.
However, there was one drawback to this new "White Steel". The problem was when young apprentices and inexperienced smiths made blades from it only a portion of the steel's potential was realized. These guys just didn't possess the skills to bring out all that the white steel had to offer. Edge retention and edge keenness were lacking. The engineers at Hitachi went back to the drawing table again to try to find a resolution to this problem.
The engineers discovered that by adding small amounts of chromium and tungsten they could alter the new steel just enough to greatly enhance wear resistance in the finished blades. Wear resistance meant better edge retention. Hitachi named this new innovation Blue steel. The great success of blue steel was that it didn't take a masterful bladesmith to bring out this attribute of edge retention in the finished blades. Average skill was all that was necessary. So long as the smith forging the steel didn't do anything wrong during the forging and heat-treating process, such as over-heating or forging while too cold, a fine blade could be produced. However, the one drawback to this steel was that the alloys chromium and tungsten affected the carbides within the steel in such a way as to reduce the ultimate keenness of edge that the white steel was widely known for.
So while white steel was regarded as the very finest Japan had to offer the cutlery world, it was openly recognized that it took a true mastersmith to realize its full potential. Blue steel on the other hand was regarded as the best choice for mass blade production by the majority of smiths. Blade wholesale dealers came to realize that large orders of blades had to be made in blue steel because the quality would not vary as much, even when the blades were forged by multiple bladesmiths. While orders in white steel had to be made by the mastersmith, hence large numbered orders were nearly impossible to fill. The other option was to enlist the help of journeyman smiths and accept varying degrees of quality.
The end result was that salesman marketing the blades, in both catalogs and other media, pronounced blue steel as "superior" because that is what the majority of their blades for sale were made from. When their blue steel blades sold out it was a simple matter of ordering more. Production of white steel blades was not as reliable or predictable, because of the rarity of capable smiths who could produce them.
In conclusion, blue steel is a success from a marketing and sales point of view, but white steel reigns from a purely metallurgical point of view when its full potential is realized.
At Carter Cutlery, after having forged and completed more than 16,000 blades in 24 years out of both steels, Murray has decided to drop blue steel from his repertoire in favor of dedicating the rest of his career to truly mastering white steel and harnessing its full potential.