Ethnographic Arms & Armour - View Single Post

Chris Evans · 18th October 2006, 05:16 AM

Hi,

I was a bit reluctant to express an opinion, because, despite being a metallurgist, I never had the opportunity to test or work with wootz steel.

All the same, Jeff Pringle is right on the ball. Based on photographs of the microstructure of wootz swords, I think it is not very useful to talk about Rockwell hardness (tests too small an area). One could obtain a better indication with a Brinell hardness test, using a Tungsten carbide indenter ball. This so as to test a greater area, which would yield a better averaged hardness value.

I should mention that hardness test results, on their own do not mean all that much, and must be interpreted in a given context. With conventional steels it is used as a very useful indicator of various mechanical attributes. However, in the case of such an odd-ball material as wootz, I am not quite sure as to what useful information could be derived from hardness readings; These would not correlate with the swords behaviour in the same way as conventional steels would. In the end, to correctly appraise wootz metal swords, the tests would have to be designed to reflect the actual application, much as Arilel described for those military swords.

I am inclined to think that wootz swords were probably better than the rest in the old days, before modern molten steel making processes were developed - Old fashioned hammer refined steels were pretty variable in their quality due to the impurities that could not be removed - Wootz was melted in the process and thus inherently cleaner, as the said impurities would float to the surface. This said, I imagine that there were ample opportunities to re-contaminate the wootz steel during the forging process.

We should remember that in the old days, swordsmiths knew precious little about metallurgy and everything was done by trial and error, with the later being much less the exception than what we are inclined to think. I feel that a really good sword or piece of steel was more a stroke of luck, rather than the rule.

Here is a good article on wootz:

http://www.tms.org/pubs/journals/JOM...even-9809.html

Cheers
Chris

18th October 2006, 05:16 AM	#8
Chris Evans Member Join Date: Mar 2005 Location: Australia Posts: 661	Hi, I was a bit reluctant to express an opinion, because, despite being a metallurgist, I never had the opportunity to test or work with wootz steel. All the same, Jeff Pringle is right on the ball. Based on photographs of the microstructure of wootz swords, I think it is not very useful to talk about Rockwell hardness (tests too small an area). One could obtain a better indication with a Brinell hardness test, using a Tungsten carbide indenter ball. This so as to test a greater area, which would yield a better averaged hardness value. I should mention that hardness test results, on their own do not mean all that much, and must be interpreted in a given context. With conventional steels it is used as a very useful indicator of various mechanical attributes. However, in the case of such an odd-ball material as wootz, I am not quite sure as to what useful information could be derived from hardness readings; These would not correlate with the swords behaviour in the same way as conventional steels would. In the end, to correctly appraise wootz metal swords, the tests would have to be designed to reflect the actual application, much as Arilel described for those military swords. I am inclined to think that wootz swords were probably better than the rest in the old days, before modern molten steel making processes were developed - Old fashioned hammer refined steels were pretty variable in their quality due to the impurities that could not be removed - Wootz was melted in the process and thus inherently cleaner, as the said impurities would float to the surface. This said, I imagine that there were ample opportunities to re-contaminate the wootz steel during the forging process. We should remember that in the old days, swordsmiths knew precious little about metallurgy and everything was done by trial and error, with the later being much less the exception than what we are inclined to think. I feel that a really good sword or piece of steel was more a stroke of luck, rather than the rule. Here is a good article on wootz: http://www.tms.org/pubs/journals/JOM...even-9809.html Cheers Chris Last edited by Chris Evans; 18th October 2006 at 09:24 AM.