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Georgian 'Bulat' technology by Zaqro Nonikashvili

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Coupon #2 ( center of the cracked bar ) has survived the oil quench and is done with one cycle of heat treating...there is no pattern yet ( as Verhoeven and Perttula predict) . I have no equipment to do the heat treating with so there is a lot of guessing. My sample is so heavily scaled, and is now so thin I will have to wrap it in HT foil as I am already less than 3mm. I hope to do another cycle tonight and get a sense of the pattern after 3 cycles. I will edit this post to add some pics.

Jan

 

Edited 2/10/ The second coupon got its second cycle by leaving it in the hot forge at temperature for a "slow" cool...the heat treating foil was too old and stiff so I clayed the blade and added a little carbon to the clay.......it worked surprisingly well.

There are clouds of cementite in the steel but to call it a pattern would be reaching.

Jan

 

 

After 5 cycles the #2 coupon is barely developing a pattern ( fine ) , lots of fine spheroidal cementite everywhere ( even in the decarb areas) ...there is also some large cementite which I suspect never got fully converted into austenite. I do not own a camera anymore ( sad face ) but thank goodness I still have my books. I will drop the topic of spheroidizing here and bring it up again in the next post on wootz.

 

Jan

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Jeff,

Don't be so hard on poor Cecil, we may see an article one of these days titled " The Exoneration of Cecil von Schwartz". There are times when I think it was possible ( would be possible ), when crucible size and ingot size are opposite extremes ( large crucible. small ingot). It is on my list of things to do this year.

 

Jan

 

Dear Jeff and Jan

Do you have any biographical information on Cecil Ritter von Schwarz? He is responsible for the first successful modern iron plant in India.

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Jeff,

Don't be so hard on poor Cecil, we may see an article one of these days titled " The Exoneration of Cecil von Schwartz". There are times when I think it was possible ( would be possible ), when crucible size and ingot size are opposite extremes ( large crucible. small ingot). It is on my list of things to do this year.

 

Jan

 

Dear Jeff and Jan

Do you have any biographical information on Cecil Ritter von Schwarz? He is responsible for the first successful modern iron plant in India.

Rajesh Kochhar

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Dear Jeff and Jan

Do you have any biographical information on Cecil Ritter von Schwarz? He is responsible for the first successful modern iron plant in India.

Rajesh Kochhar

 

 

Rajesh,

I was not aware of that information, thank you. I have no specific information but often run into the name when google ing books , 19th century, free books...then enter his name and "wootz" or Indian crucible steel.

 

Jan

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I believe Ric asked me about von Schwarz and I tried to find something here from Germany:

the only things I could find was the following:

 

Cecil, Ritter von Schwarz has been mentioned in a book by Glasenab on the chemical knowledge of the hindus (or by PC Ray 1919?)

he has also been mentioned in:

Internationaler Binnenschiffahrts-Congress in Paris 1892 Heft 12 Cecil Ritter von Schwarz: Ueber die Eisen- und Stahl-Industrie in Ostindien (on the iron and steel industry in east india)

someone is selling a book where the article is in, but it is 158€

http://www.zvab.com/Zeitschrift-Oesterreichischen-Ingenieur--Architekten-Vereins-Vierundvierzigster-Jahrgang/151016345/buch

I do not know if this up to date anymore though!

 

his Family has probably lived in Hallein, Austria

Ritter v. Schwarz-Straße 11, 5400 Hallein

it is a street named after one of the family

Edited by Jokke

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ame='Jan Ysselstein' date='15 January 2012 - 04:05 PM' timestamp='1326665114' post='205634']

 

Two of the ingots are now bars at about7-8mm thick..each will be ground to remove pits, laps,cracks and other potential hazards. Both bars look promising, though the patterns are relatively fine. Clean the bars, forge the bars and pay attention to cleanliness at the hammer... and etch .

At this point I think I have eliminated some of the problems encountered during the processing of the cast ingot. Some remaining obstacles are, forging to develop an interesting pattern, heat treating andthermal processing to get the best combination of good looks and strength.

I will post some pictures when I am done.

 

Jan

 

The photo below is of bar #1 a very fine structure not unlike some of the photos and samples of Indian steel I have seen. The spheroidizing was done at sub critical temperatures just below critical...now that I have some pics of the sample I am free to explore other temperature ranges for spheroidizing ( I will post a pic later).

The pictures represent the middle and end pieces of a bar approx. 45 cm long cut into 3 pcs. , one of the pieces did not survive a quench.

 

 

Jan

Edited by Jan Ysselstein

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Hi Jan

 

those black lines in the pic on the right.. I have these pop up in my wootz, and i'm not quite sure what their origin was ?

 

you can see some pattern starting to work on the right

 

and just as you have mentioned, i've seen similar wootz...

 

the coupon that didn't make the quench... you could heat cycle that one .. say up to Acm and down to bellow non-mag and use that as a control ... and the others are going for differing spheroidal treatments ... it'll be very interesting to see them all together..

 

Jan, do you think these bars would have a low level of P in them ?

 

 

thanks for posting

Greg

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Hi Jan

 

those black lines in the pic on the right.. I have these pop up in my wootz, and i'm not quite sure what their origin was ?

 

you can see some pattern starting to work on the right

 

and just as you have mentioned, i've seen similar wootz...

 

the coupon that didn't make the quench... you could heat cycle that one .. say up to Acm and down to bellow non-mag and use that as a control ... and the others are going for differing spheroidal treatments ... it'll be very interesting to see them all together..

 

Jan, do you think these bars would have a low level of P in them ?

 

 

thanks for posting

Greg

 

Greg,

 

There is a lot of pattern in both but everything is so closely packed and hard to see...this is bar#1 and #1,#3 and #5 should all have some P as they come from the high P bloom....but if I like the pattern I will have the sample tested again. None forged like the very high P ingots of the past.

 

"those black lines in the pic on the right.. I have these pop up in my wootz, and i'm not quite sure what their origin was ? " I have often wondered that myself.

Regarding the alternative spheroidizing methods John Verhoeven has both systems in his books..there is a conflict between the dirty soldier's coat process and the Captain's observed process, I will check it out and pots it. I know the DET process will give me fine cementite but I would like to work in the cooler realm as well. Here some temp controlled furnace would be interesting.

#5 has just been forged by hand for an hour and looks about the same as the cake did when it came out of the crucible. I caught and fixed two problems ( I hope) liquid sparks were coming out of the shrinkage cavity and the rim had a crack which I just happened to see. I will post a pic....#5 is my best hope for an interesting pattern.

 

Jan

Edited by Jan Ysselstein

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Greg,

 

Here are a couple of pics of #5 hand forged..I will be melting some 2kg ingots this week end and cannot forge them by myself..( my hammer is down so melting and heat treating is in).

Jan

side view

top view

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yes.. as the ingot cools it pushes a higher concentration of alloy away from the chillzones... i believe the shrink area is the last to solidify ...under that assumption, i believe that area is the most highly concentrated and therefore would have the lowest melt point (mp)... after a couple of heats and the carb distributes its self a little better, the center should be less cranky

- still it can pop up at anytime.. little cracks n such .. in that case, those cracks are gouged out asap and forging is continued ( Jan, i know you know this... but i write it to help those that may audit this post )

 

 

very good idea to have the samples come from the same bloom.. i think that is a great control of variables

 

myself, i just look at the verhoeven idea of cycling as just a way of cementite coarsening ... i don't know if it can do what Niko does... with areas filled with fine globes of cementite ... ... if you work the bar at cooler temps, i imagine you'll need the hammer running... as you know this stuff is quite hard to move at low temp..

 

good luck on the forging!

Greg

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yes.. as the ingot cools it pushes a higher concentration of alloy away from the chillzones... i believe the shrink area is the last to solidify ...under that assumption, i believe that area is the most highly concentrated and therefore would have the lowest melt point (mp)... after a couple of heats and the carb distributes its self a little better, the center should be less cranky

- still it can pop up at anytime.. little cracks n such .. in that case, those cracks are gouged out asap and forging is continued ( Jan, i know you know this... but i write it to help those that may audit this post )

 

 

very good idea to have the samples come from the same bloom.. i think that is a great control of variables

 

myself, i just look at the verhoeven idea of cycling as just a way of cementite coarsening ... i don't know if it can do what Niko does... with areas filled with fine globes of cementite ... ... if you work the bar at cooler temps, i imagine you'll need the hammer running... as you know this stuff is quite hard to move at low temp..

 

good luck on the forging!

Greg

 

Greg,

Thanks, for the suggestion...I think it is a kind of interesting puzzle ..I may have done the reverse at one time ..converted the cementite in the dendrite to fine spheroids. I will see if I still have a pic...if i recall P played a role in that bar. I heated this ingot up prior to pulling it..I think I will just hang at 1000 next time...diffusion to the forge....I may cycle to room temp a few times on future runs...I do see cracks and signs of cast a iron nature.

 

Jan

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Greg,

.I may cycle to room temp a few times on future runs...I do see cracks and signs of cast a iron nature.

after a couple of heats and the carb distributes its self a little better, the center should be less cranky

- still it can pop up at anytime.. little cracks n such .. in that case, those cracks are gouged out asap and forging is continued ( Jan, i know you know this... but i write it to help those that may audit this post )

Jan

 

Greg,

Thanks for the heads up here...I am losing it bit by bit ( hand forging )....tomorrow ( if my shoulder holds up) I will try to get a bar and check pattern....it does seem to cat iron again...not by intent i just do not have any control over the process yet.

 

Jan

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Greg,

Thanks, for the suggestion...I think it is a kind of interesting puzzle ..I may have done the reverse at one time ..converted the cementite in the dendrite to fine spheroids. I will see if I still have a pic...if i recall P played a role in that bar. I heated this ingot up prior to pulling it..I think I will just hang at 1000 next time...diffusion to the forge....I may cycle to room temp a few times on future runs...I do see cracks and signs of cast a iron nature.

 

Greg

Well , I think I have reached a point where I should stop for the day...my shoulder tells me....some cracking is happening and the normal transition to softer material is much slower. I will finish on the hammer and really only need a picture of the thin forging for the record. The ingot, now a small bar ( lots has been lost to grinding, cutting and falling off)...needs to be reduced to 1/4 its current thickness.

 

Edit,..... By the way spheroidizing fine cementite without large fragments of cementite dominating the game is not as hard as one may think. I will do it soon, and post.

 

So, out of 8 successful melts we have two successful forgings ( and a fragment of forged cast iron, 4 cast iron ingots I do not dare to touch, 1 museum piece)... a bit of knowledge and experience and hope it will go better next time. Going to look at the Fe/C phase diagram again and target a C level for the next set of melts (melting together steel of known C level) just to see how that steel works and to test the durability of the crucibles at higher temps.

I will disconnect from this post again.

Jan

 

Edited by Jan Ysselstein

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Klaas,

I am almost finished here...the cast iron forging above has not been discarded and we still need to see the results of the war between the components of that structure during heat treatment.

All heat treating will be done after the next set of ingots are forged.

The ingots have grown and are now big brothers to the younger 700 gram little ones...1200 and 1500 grams. An even bigger brother should come home in a day or two and he is 2300 grams. Some of these big boys may not stand up to forging..we will see. We are now ( will soon be) at an ingot size (1500 to 2300 grams) large enough for a sword.

The middle ingot is made mostly from an ingot made earlier on this thread ..a little micronutrients were added ( I had guessed that at 1.6%C,which must have been lower than it actually was).

I have read your paper on wootz and think you did a very good job, good luck with your new shop.

 

The fact that this post has not inspired people to use Zaqro's methodology is a bit puzzling to me..it is so simple and so clear...

Jan

Edited by Jan Ysselstein

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Not having seen much wootz discussion here lately ..I thought I would post some pictures of what I am seeing, while looking at some recent ingots. I am still working on this topic so I thought I would post it here. These may not be shrinkage cavities.

Jan

 

 

 

 

 

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So

 

I started making bulat again.. For starters I used the Georgian method, but didn't add enough charcoal in the crucible, or maybe it did not get hot enough.

Got a small cace out of it with small dendrites in each direction. This one was a dream to forge, and did not have a lot of carbon in it (because the fusion was not completed). However I just forged it out to get the feeling going again. After about 100 cycles I managed to make it in a rough knife. The rest I sanded of. Way too much sanding. With the hardening something weird happened. There are three temperlines, I don't know how I did that. Also, there is a 'cloud' of what seems to be very small cementite pattern. The big pattern dissapered with tempering, some of it still remains in the untempered parts and in some parts of the hardened steel.

 

There is a crack somewhere, the steel sounds crooked. Also, I should learn not to use white glue with such a beatifull snakewood.

 

Anyway, it was a great exercise, and really got me up for the next one.

 

1013320_10152204652061897_216505998_n.jp

1653348_10152204651521897_828168774_n.jp1796545_10152204651406897_246556018_n.jp1959563_10152204652066897_989829714_n.jp1779950_10152204651026897_515067050_n.jp1896747_10152204651086897_947268714_n.jp1796563_10152204651851897_109143194_n.jp

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Klaas Hi.

 

I love those crucibel, ingot pics...really nice.

Also the blade has nice shape...bit sad thing that uneven melt..But Im glad to see you melting Wootz :lol:

BR

Niko

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Thank you for posting it.....I am looking forward to reading about it.

 

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That is beautiful. Thanks for showing.

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Wile waiting and looking forward   to  the technology presentation .. I think I will go for it as well..I need an ingot of 1800 grams to make a sword. So the criteria are ..a large ingot, a solid sound ingot and the patience/luck to forge it ( no my name is not Peter ) to a pattern. The large ingot should cool nice and slow for maximum dendrite size. Right now I am just forging old ingots to see if I can avoid breaking them.

 

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