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Gt Obach · 11th April 2005, 02:40 AM

hi
i guess my post may have been a little confusing... it is tough to find a source of error as to why the wootz may have been brittle in the northlands...
- retained austenite is just one possibility..
- grain growth during forging is another.. (if you forge at too high a temp for too long, it will encourage the crystal structure in steel to grow large-- this can make a blade brittle)
-stress in the steel..... if the steel is forged bellow non-magnetic, stress is put into the metal and this can make it brittle
- quenching a blade in an aggressive quenchant can also put lots of stress in the steel... it can lead to cracks.... this may not be apparent till later when the sword is used ....
-inclusions in the steel can also weaken it...

so as you can see..... there are several possibilities to having brittle steel ...... and lot's of it involve the smith and the way it was forged and heat treated

I have read the Persian steel book.....it is very interesting.....in there you will find a part that says some swords were quenched in hemp oil and fat.... or by other means.. there are many ways to heat treat wootz.... it all depends on the structures you want...

i've seen several persian swords with a quench line....where the sword etches darkly on the tempered martensite and very litely on the untempered side.....
-- i know this because this is exactly what happens with my blades... since i prefer to oil quench

I have made some swords of wootz.....and they all worked well.... preformed similarly to 5160 .... which is all I can tell
- I've chopped some of my bowies into 1/4 plate iron... (the are very large bowies.....since i like foot long blades).... and they handled the iron with good effect..... cutting a series of 1/8 inch gooves and no cracks or blade chips..

I haven't noticed any weakness due to pattern... ... sometimes as you hammer an ingot out.... you will get these large cracks... almost like delaminations ..... and my solution to this problem is to grind them out with a 6inch grinder......then forge it flat and keep going......
-however this give you a crazy pattern... since it has cut through some of the sheeting..... yet it will still make a dandy knife
- the prophets ladder can be made by grinding ladders in and forging flat.... and this pattern has shown no problem with cutting

I have a feeling that bulat is a little different....just by looking at the steel I feel that some of those blades are alloyed with different elements... their etch is different...
- how ever I don't think the bulat is weak or cracky..... i believe it can be if you don't roast your ingots before forging them out...
-I've had more problems with crackiness with those kinds of ingots..... and the pattern is much denser

I will try to email Visily and see if he finds his bulat is brittle in the cold..

Greg

I also agree that alloy could affect how it functions in cold

11th April 2005, 02:40 AM	#11
Gt Obach Member Join Date: Mar 2005 Posts: 116	hi i guess my post may have been a little confusing... it is tough to find a source of error as to why the wootz may have been brittle in the northlands... - retained austenite is just one possibility.. - grain growth during forging is another.. (if you forge at too high a temp for too long, it will encourage the crystal structure in steel to grow large-- this can make a blade brittle) -stress in the steel..... if the steel is forged bellow non-magnetic, stress is put into the metal and this can make it brittle - quenching a blade in an aggressive quenchant can also put lots of stress in the steel... it can lead to cracks.... this may not be apparent till later when the sword is used .... -inclusions in the steel can also weaken it... so as you can see..... there are several possibilities to having brittle steel ...... and lot's of it involve the smith and the way it was forged and heat treated I have read the Persian steel book.....it is very interesting.....in there you will find a part that says some swords were quenched in hemp oil and fat.... or by other means.. there are many ways to heat treat wootz.... it all depends on the structures you want... i've seen several persian swords with a quench line....where the sword etches darkly on the tempered martensite and very litely on the untempered side..... -- i know this because this is exactly what happens with my blades... since i prefer to oil quench I have made some swords of wootz.....and they all worked well.... preformed similarly to 5160 .... which is all I can tell - I've chopped some of my bowies into 1/4 plate iron... (the are very large bowies.....since i like foot long blades).... and they handled the iron with good effect..... cutting a series of 1/8 inch gooves and no cracks or blade chips.. I haven't noticed any weakness due to pattern... ... sometimes as you hammer an ingot out.... you will get these large cracks... almost like delaminations ..... and my solution to this problem is to grind them out with a 6inch grinder......then forge it flat and keep going...... -however this give you a crazy pattern... since it has cut through some of the sheeting..... yet it will still make a dandy knife - the prophets ladder can be made by grinding ladders in and forging flat.... and this pattern has shown no problem with cutting I have a feeling that bulat is a little different....just by looking at the steel I feel that some of those blades are alloyed with different elements... their etch is different... - how ever I don't think the bulat is weak or cracky..... i believe it can be if you don't roast your ingots before forging them out... -I've had more problems with crackiness with those kinds of ingots..... and the pattern is much denser I will try to email Visily and see if he finds his bulat is brittle in the cold.. Greg I also agree that alloy could affect how it functions in cold Last edited by Gt Obach; 11th April 2005 at 02:51 AM.