Some Thoughts About Steel

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Hi Folks,
I will try to give a short bit of information from the little I have been able to absorb. Steel, of course, is a mixture of a small amount of carbon with iron. Other elements may be added, or were present in the original ore, which allow the steel have differing properties. Steel-Wikipedia

So now what?
Forging: The simplest definition of forging I can give is the hammering upon a metal while it is heated to allow it to be plastic and able to be formed. It also homogenizes that metal so that the entire piece is of the same material and content of elements that were in the original melt. Forging-Wikipedia

Hardening and tempering: Heat Treating-Wikipedia

Now here is the real secret of razors. The early sword steels were more of a wrought iron than true steel, as were the cutting tools such as knives and razors. Wrought Iron-Wikipedia

As such, while having a great improvement over iron as a usable tool they had too much carbon to take a good hardening and tempering to make a combination material that was very hard to hold an edge and resilient to flex rather than break. Over the ages, various peoples had access to different ore deposits and developed various methods of forging that iron into steel.

There was WOOTZ, a crucible steel from the Asia Minor area which was made by adding iron and carbonaceous material s together with a frit / fluxing agent into a clay pot which was sealed air tight and heated to the highest temperature the early forges could produce and held there for a long period of time. I may also state that some but not all of the Viking blades were made by a similar process. Some folks also consider this to be the original "Damascus Steel". Wootz Steel-Wikipedia

Then about the same time; B.C.E. to early ~1700 C.E.; the method of folding and hammering layers of good steel came to be used. Wenow call this Damascus steel, pattern welded, or layered steel. It was the main component of cutting tools throughout Asia and much of Northern Europe. Wootz Steel-Wikipedia

None of that quality steel, so skillfully wrung form the earth and beaten into submission, would be any use, but for quality hardening and tempering. The usual methods of hardening of course were heating the metal to a high red heat and plunging it into either water, brine, or some form of organic material or liquid. Yes, Johnny, the tales of blades being quenched in human flesh are not all legends! Oil, though, was a lot cheaper! How it was done improved the quality of the steel and its edge holding ability.

Many early steels were salt brine quenched and they became very hard but they could be brittle if anything went wrong with the process.  An organic oil would add carbon to the surface of the steel and allowed a little better control of the process.

Another process was case hardening which hardened the surface of a soft steel or wrought iron to a very hard and wear resistant layer up to 1,5mm or about 1/16th of an inch. Case Hardening-Wikipedia

Now cutting to the chase; if you will forgive the pun? Ok you now have all the elements of the processes;

• Swedish iron ore was the best to be found.
• Many early razors were case hardened and Sheffield was among the best at this process to about 1820's.
• Along with this came better understanding of oil hardening and tempering and took over the trade after about the
   early 1800s.
• The Swedes developed a process for producing and hardening thin steel strips. They produced the clip back
   frameback razors there and the steel which allowed others to make them also.
• That popularized the Frame back razors we know from the 1860s onward to the present day.
• In Switzerland a family invented the removable blade Frameback razor;
   ( I recently found that Msr. Le Coultre is said to have melted and reforged watch spring material to get a consistent proper steel for his blades)
   yes he was That Le Coultre! Watches.

Aha! Thin hard steel! Voilá
About the early 1880's some folks started to make what we now call safety razors with hollow ground replaceable blades. As the quality of strip steel became more uniform and repeatable the first razors with thin steel replaceable blades came into being. Those blades were about a half mm thick or about 1/64th of an inch. As the processing of the strip steel improved further the blades became thinner and could be stamped out, hardened and tempered, and honed in a long ribbon and then snapped from the ribbon into the individual blade s we have become familiar with.
Then about the early Twentieth Century, the process of making stainless steel came into being. This process was shelved for a time, because the early steels made were susceptible to, of all things, vinegar! Stainless Steel-Wikipedia

As years pass the steels become better, the processes more particular in their requirements, and the new instrumentation allows even better control of the whole progression from the original ore's and elements to final shaving products.

I am led to really respect the unsung geniuses of forgotten in history that really made the mistakes which they found to make a better product. Their genius is that they remembered what went wrong and they could duplicate that change in the process after they found they has\d discovered a better way!

The old idea of trade guilds, with their apprenticeship programs is passing away because it no longer takes seven years to learn only the basics of a total ore to finished product. It also took a lifetime to learn it well!

Just my take on the subject. Sorry to be so long winded. Maybe!
Member- Geezer, of Straight Razor Palace

And Further:
Just some small things to think about before making blanket statements about so and so's steel and its quality and abilities!
Iron becomes steel and hardened steel through changing the size of the grain and the quantity and type of carbon contained. There are and have been many processes which did this to a greater or lesser degree of success. A while back, I was able to enjoy a pleasant conversation with a long established (46+ years) expert welder and restorer of edged weapons, armor, and fire arms for museums. I guarantee that he knows more than a bit of modern and ancient metallurgy! His opinion, from his experience, is that there are so many variables in older steel manufacturing that any pre 1900 blade is apt to be a tossup and even some since then!
There were manufacturers and smiths that used processes similar to those now in use and others that probably did not!

Some, for instance:
The Crucible steel production method of Sheffield and others and earlier, of The Ottoman Empire (Wootz) and in some cases the Nordic and Germanic peoples was a great way to make quality steel in small quantities. It also took a week of careful heat control and a good bit of legerdemain with carbon in the form of charcoal, iron ore selection and preparation plus addition of wrought iron and the stirring in of elements at the proper time to do it well. (Some other methods were wrought, folded steels)

Much of the difference of early steel qualities was due to the iron ore and where it was mined/found/ reduced from sand. The included chemicals and elements would, of course, vary from site to site. Much of the quality steel of northern Europe was from the Nordic areas. The Arabic, Northern African and Mediterranean areas had their own ore sources and the Japanese used hematite; a sand.

He also pointed out that some of the Wedge blades we think are ground off center to the spine were probably caused by the owners sharpening through the case hardening at the bevel and so from then on they only honed one side to keep the hard surface all the way to the edge. He has seen this effect on old knives such as butcher knives. It may show up as a line of differently oxidized steel above the bevel on some blades.
According to him, there were many knife, sword, and cutlery manufacturers who used pack case hardening* well into the late 1800s; a process that turned the surface of a poor steel into a steel capable of taking and holding and edge.. If done properly, the hardness went into the metal about 1.5mm or 1/16th of an inch. It also left a relatively soft and flexible core in the blade to absorb shock. A simple way to explain the effect there is a tale of a armor-smith's apprentice who accidentally dropped a helm of iron wrapped in leather into a forge. It became surface harder than they had ever done before. Yup, you and I know the apprentice got beaten and may have been thrown out rather than rewarded. How so ever, the tale is a common one in historical fiction.

So, a bit of knowledge will help understand some of the historical possibilities inherent in a great material that made modern civilization, cleanliness, and large scale war possible. It is a green material in the modern parlance and may be reheated, re-alloyed and reused, to any required effect.

Pack case hardening is used to take a low carbon content steel to a higher surface content of carbon capable of hardening and tempering. It is done by placing the by low to medium carbon steel/wrought iron** into a thick walled airtight iron box with certain types of charcoal, animal hides, tanned and otherwise, and horn and bone scraps by use of eyeball quantities and TLABR ( That Looks About Right), and assorted chemical additives. Some of them like arsenic really helped the final quality and some were somewhat imaginative; silver for instance, a good example of early hype!! The box and contents were placed into a forge type forced draft oven/kiln and kept at high heat for up to a week. This allowed the carbon to ‘soak’ into the steel without being burned out of it by oxygen. The amount of time and temperature control greatly affected the final result. The methods were mostly eyeball, mark 1. The resulting steel and all contents were then dumped into hot water, brine, or oil. That hardened the steel. It was then tempered. Or by some methods it was used to harden only the very surface of tools and or gun parts to withstand abrasion.

You can see beautiful blue/gold/red/brown color case hardening on many quality firearms and quality tools for the shop and mechanic from early days to the present day... for more info, see Case hardening-Wikipedia

Wrought iron is iron which has been processed by heat and forging into an iron with a much smaller grain size and carbon content. It also has inclusions of slag. It was an iron we may call wrought but was also known as malleable (for cold and hot working and wieldable. Much less brittle than grey iron.) For more info, see Wrought Iron-Wikipedia

It was only a short conversation; it could have gone on into a month and year. I look forward to more of such conversations when we get together at a similar venue in six months. I was able to verify some of the things which I had wondered 'bout. He asked me about some things with which I was familiar, at least in theory, and I was able to point him to some re/sources I had used in the past.

Nothing we do has a short answer which will suit all cases of a subject and I have been burned many times by believing "Gospel according to some practitioner.

I look forward to comments upon this short bit of shared information.

~Richard SRP member name "Geezer"

AND: Here are a few links with lots of information in the quick versions and videos.

Materializing Sheffield - Steel City: an Archaeology of Sheffield's Industrial Past

Materializing Sheffield- Steel City