GniCr40Al4 Hunter

Cool stuff that helps. regardless of whether or not this makes a good knife material its an awesome learning experience. Give me a bit to digest this latest information, i'd rather have too much, than too little
 
There is a bit of a language problem there .
The Ni3Al precipitates and there is coherency with the matrix .That is a strain field which strengthens in addition to the precipitate itself. This is what we see in the secondary hardening of steels containig significant amounts of V, Mo, W.

My previous point was that these things have to be researched carefully for each alloy .There can't be any guesses.
 
mete said:
There is a bit of a language problem there .
The Ni3Al precipitates and there is coherency with the matrix .That is a strain field which strengthens in addition to the precipitate itself. This is what we see in the secondary hardening of steels containig significant amounts of V, Mo, W.

My previous point was that these things have to be researched carefully for each alloy .There can't be any guesses.
Click to expand...

without research every thing of the alloy myself i would not intruduce it to other people.

as mechanism of precipitation hardening, there are many similarites between Ni3Al precipitates and the secondary hardening from MC/M2C carbides during the tempering. but its not the same.

1) as for ferrous steel, quenching cause significant phase trasition, combine over satiated martensite, dislocation of substructure strengthening all together, it strengthens and hardens the metal.

2) for this specific Ni-Cr alloy, the hardness and strength doesn't increasing after the solution. solution at 1200 C then cooling in water does not harden nor strengthen the alloy at all. it result single phase austensite, it soften the metal make it easier to be work with. and giving the cold work potential to futhur refine the grain and ni3al precipitates during later aging.

quenching or solution of this alloy do not increase its hardness. and the aging is the first hardening, not the "second".

conclusion, for this specific alloy, solution does not do the first hardening. so "secondary" can not apply here. its the aging that harden it into a real man.

mete said:
Not edge packing at all , just work hardening the edge .Just like they hardened the edges of bronze and iron blades thousands of years ago.
Congratulations -- you've just reinvented the wheel !!
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nope, the work hardening does not increases its hardness to hrc67. cold deformation absorb the strain energy, and gives the potential for later recrystalization combined with aging that increase its hardness. and whats the matter of reinvent the wheel that might revolute the knife making history. when ferrous did not satisfiy my ambition, i sought the revolution. so should every person who endures the evolution.
 
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I got my sample in today. It's tough, pretty springy but will take a set after about a 15 degree bend, and is totally nonmagnetic. Didn't really get to play with it yet, probaby next week. Thanks Xiachu, hammerfall.
 
did you aging it before doing the bend? the sample you received is solution condition. it has no springness as it is now. you need age it at 630 C for 5hours to show it true self.
 
Nope, just wanted to experiment with it in solution. It's a new metal to me and many others, to me it's properties in any condition are part of the whole picture of the material that I'd like to observe.
 
hammerfall,
Will you be able to offer this metal in pre-rolled cold work reduction?
Seems like it could have some interesting possibilities in 2mm thickness at the higher hardness range.

Also, will working the metal ( grinding and sanding) after the reduction and age hardening affect the hardness ?
 
bladsmth said:
hammerfall,
Will you be able to offer this metal in pre-rolled cold work reduction?
Seems like it could have some interesting possibilities in 2mm thickness at the higher hardness range.

Also, will working the metal ( grinding and sanding) after the reduction and age hardening affect the hardness ?
Click to expand...



now I have a 2 mm thick alloy board.
It is from 5 mm to 2 mm cold rolled directly, because the damage to the device is relatively large, so the workers are only processing a piece of me.
I did cut a small piece of hardening, the hardness after the detection of about 62.
However, the size of this plate is too small and can not be cut out of the test samples. Unfortunately this can not be measured to you again.
Although I would like to give your piece of the board after a cold.
 
Salem Straub said:
I got my sample in today. It's tough, pretty springy but will take a set after about a 15 degree bend, and is totally nonmagnetic. Didn't really get to play with it yet, probaby next week. Thanks Xiachu, hammerfall.
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You're welcome.
The size of a bit smaller.
Because there are only so few materials on hand.
I would process the alloy more as i have the opportunity。
 
bladsmth said:
hammerfall,
Will you be able to offer this metal in pre-rolled cold work reduction?
Seems like it could have some interesting possibilities in 2mm thickness at the higher hardness range.

Also, will working the metal ( grinding and sanding) after the reduction and age hardening affect the hardness ?
Click to expand...

hi stacy. cold roll to 60% reduction is possible but relatively hard to achieve.

grinding and sanding usually would not effect the final hardness after aging. unless pressed too hard and stays above 700C for long time.

as a knife blade, cold die forging or cold forge might be a good idea. cold forging by hand is relatively easy to do, a noob like me on the first try can still manage hammer a 1.6mm edge from a 5mm bar. i did that out of curiousity. xiachu WEDM the bar to a blade shape. i then smite it hard to form a edge. dispite my noob forging skill, the bronze age technique works just fine lol.

coldforge.jpg


coldforge%20section.jpg


now i got to grind out the hammer mark. age it. then take a hardness test to see if my caveman technique can give the desired result.
 
yeah and you all can laugh at my forging skill lol.

i could have sent it to a professional to do the cold forging, but i just too lazy to go to post office.
 
well, my goal is to differental cold deform the blade, in order to get a differential hardened blade after aging.
 
The forging looks ok. When forging steel hot, you prebend the stock downward so the upward curve imparted by forging the bevel brings the blade back to the profile you want. The only way to do that here would be to have xiachu WEDM a precurved shape.

In this case, you've merely made a skinner blade.

I'm interested in the resulting Rc after aging. Will you test it at different parts of the edge to see if the cold forging affected it fairly evenly?
 
Salem Straub said:
The forging looks ok. When forging steel hot, you prebend the stock downward so the upward curve imparted by forging the bevel brings the blade back to the profile you want. The only way to do that here would be to have xiachu WEDM a precurved shape.

In this case, you've merely made a skinner blade.

I'm interested in the resulting Rc after aging. Will you test it at different parts of the edge to see if the cold forging affected it fairly evenly?
Click to expand...

thank you, salem. thats a good idea. i had no expeirence of any smith work. i have a lot to learn from people here haha.

and of course, that was the goal. first, to test if differential cold deforming in solution condition can achieve differential hardened blade after aging. second, test how the hardness contribute from edge to spine.
 
Looking forward to see how this unfolds and am wondering about the eveness of the readings you may get at the edge too. Any progress on that blade Stacy?
 
mete said:
There is a bit of a language problem there .
The Ni3Al precipitates and there is coherency with the matrix .That is a strain field which strengthens in addition to the precipitate itself. This is what we see in the secondary hardening of steels containig significant amounts of V, Mo, W.

My previous point was that these things have to be researched carefully for each alloy .There can't be any guesses.
Click to expand...

岂止ni3al，任何析出相在基体析出都会导致晶格畸变，从而产生应力场，固熔在基体中的合金元素同样产生晶格畸变产生应力场。而应力场会强化材料能强化材料这种道理就象1+1=2那么简单，我想无论是hamerfall还是xiachu都不会去强调这么简单的问题。

这些是中文，如果看得懂并且有什么想说的请也试试用中文回复，xiexie!
 
Nothing new yet.
I have to finish out 40 oyster knives and 15 other knives for a private showing Sunday, so this weekend is booked.
 
I hardened the blade by heating to 1205F and soaking for 12 hours. It seems noticeably harder. I would guess about Rc 57-58, but will have to test it when I get a chance.
 
This alloy is very strong in the plastic before aging, it can be relatively easily part with a hammer to knock the blade flat. can increase the hardness of the edge part after cold deformation
 
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