Book Review – Damascus Steel Swords: Solving the Mystery of How to Make Them

[Larrin]

A review of a new book from Dr. John Verhoeven about the work performed on solving the mysteries of wootz damascus. It's a fun little book. If you want to learn more you can read the review.

https://knifesteelnerds.com/2019/02/04/ ... make-them/

[awa54]

Thanks for that video link!

it's a fascinating subject

[elena86]

John Verhoeven is a great metallurgist. He is behind the idea that AEB-L is one of the best allaround steels for knife blades. Reproducing the misterious Wootz steel is indeed a fascinating journey.

[TazKristi]

A review of a new book from Dr. John Verhoeven about the work performed on solving the mysteries of wootz damascus. It's a fun little book. If you want to learn more you can read the review.

https://knifesteelnerds.com/2019/02/04/ ... make-them/

Very interesting info! Thanks for sharing Larrin. I'm going to move this over to Off Topic since it's not about a Spyderco product but it is cool info just the same.

Kristi

[awa54]

another take on damascus, possibly at odds, or maybe complimentary?

https://skullsinthestars.com/2011/09/01 ... echnology/

[Larrin]

another take on damascus, possibly at odds, or maybe complimentary?

https://skullsinthestars.com/2011/09/01 ... echnology/

I don't buy the carbon nanotubes information and either does Verhoeven: https://www.nature.com/news/2006/061113 ... 13-11.html

[SpyderEdgeForever]

I would like to get his book and read it for the info. But with all due respect to both he and you, Larrin, they have experimentally seen the carbon nanotubes inside the steel matrix. Infact,I could show you proof/evidence. It is metallofullerene and it was patented years ago by a man named Robert Job.

https://www.prnewswire.com/news-release ... 70098.html

It is called Rhondite.

https://en.wikipedia.org/wiki/Rhondite

"Rhondite is a nano-scale helical carbon-based structure created by Robert Job that may be used in the production of steels and alloys to increase hardness, strength, ductility, and wear resistance. Each helix is actually made up of small spheres called buckyballs or fullerenes.

Each fullerene sphere contains metallic atoms inside of the carbon cage; and as such have created a subset known as metallofullerenes. It is the chaining and winding of the metallofullerenes into their natural shapes that produces the unique Rhondidic structure.

Manufacturing process

Rhonditic steels contain about 0.35 to 2.25 percent carbon by weight. They are formed by mixing a high carbon and low carbon steel, such that the mixture as a whole has the desired carbon content. The mixture is then heated to a temperature at which the high carbon steel will melt, but kept below the melting point of the low carbon steel (~2750 F). The mixture is slightly cooled then maintained for time sufficient for the carbon present to form fullerenes and fullerene chains (approximately 15 minutes), and finally allowed to cool to room temperature.[1]

Rhondite is:

Used as an additive
Takes the place of free carbon
Chemically similar to standard metals
Increases strength without tempering or quenching
Named after Robert Job's wife

Here is an excellent article on this:

https://web.archive.org/web/20090628180 ... apr99.html

Verhoeven's problem seems to be that he thinks that the carbon nanotubes do not add any special properties to the steel, because he clearly admits they are there. He cannot deny their existence. Some metallurgists as well as specialized physicists doubt this because they think carbon nanotubes can only be produced in high energy laser furnaces or electrical arcs and not in steel melts. Job has shown otherwise.

Job has shown actual photomicrographs of the carbon nanotubes/buckywires in there.

It makes perfect sense. The nanotubes act as microscopic diamond teeth that adhere to the matrix and that is how the sword edges cut so well.

[Larrin]

I’ve read the journal articles claiming carbon nanotubes in steel. They have no good evidence.

[Larrin]

For those who are interested, here are the articles:
http://www.hefajstos.agh.edu.pl/files/% ... eibold.pdf
http://www.hefajstos.agh.edu.pl/files/[ ... eibold.pdf

[SpyderEdgeForever]

Larrin, I also want to say that I have great respect and admiration for you and your work. I want to get a copy of this book because I love the topic and knowledge.

I have a question for you and others about Damascus steel. While many prefer to get that patterning, can a blade or object made of this be polished to have a satin/satiny sheen and finish, if one wanted the functional properties of Damascus steel, without the etched patterns, or, are those not able to be polished out?

[awa54]

On a far less interesting note, are there modern crucible steels that equal the properties of true Damascus steel, or does the special crystal structure that is created by the process confer superior flexibility to edge retention ratios compared to "conventional" mono steel of a similar elemental makeup?

[JD Spydo]

Well Larrin you've put up another most interesting topic. Now I'm not a big fan of damascus blades per se>> even though many of them are really pretty to look at. Even though I will admit that most damascus blades have a lot of aesthetic appeal. But to me I'll take function over perceived beauty any day of the week.

However it does bring up some questions I've had about Damascus steel for a long time now. First off what are the functional advantages of damascus if any? Also is stainless damascus the same animal as high carbon steel damascus?

I have been told throughout the years that most damascus blades have significantly more tensile strength>> is that true? I've also been told that most damascus blades have good corrosion resistance>> is that true?

Again Larrin I find just about all of your threads to be extremely interesting and thought provoking :)

[TomAiello]

Larrin, do you happen to know if the Roselli "Wootz" (https://www.roselli.fi/epages/roselli.s ... lin_tarina) is the same as the historical damascus steel?

In 1985, Heimo came across an interesting study by Stanford University. The study involved describing methods that dated back more than 2,000 years and enabled making factory-produced steels much more durable than the modern varieties. One of the most common names for these old, durable steel grades is ”WOOTZ”. Heimo concluded that since this age-old grade of steel was “birthed” by blacksmiths, so it was similarly his duty to acquire this skill via a “hands-on” process. After fifteen years of experimenting the results were impressive, and this particular grade of steel finally entered into industrial production with the help of a top researcher in the field. Nowadays it’s called ”UHC (Ultra High Carbon) WOOTZ” - a steel grade completely different from the rest. The present-day UHC steel by H Roselli is a non-alloy, ultra-high carbon steel. Its achievable hardness is 68 HRC. The ultimate tensile strength is 2500N/mm2. Combinations of corresponding hardness had not been previously detected, and the steel also had remarkable dynamic ductility. Optical equipment is unable to detect any grain boundaries in the steel, which enables excellent characteristics.

[SpyderEdgeForever]

Tom that is amazing, thank you. JD: Why are you not a big fan of Damascus steel?

Also: As with all steel, all Damascus steel is not equal? How do we determine if particular wootz knife is good or not good?