It seems, for the most part, to be a case of confusing cause and effect by folks trying to explain observations in the past without the means or knowledge of what is happening during the forging process. Most of the explanations I have seen are mere assumptions that are physically inaccurate or impossible regarding the mechanisms at play which are cited. I believe the majority of the effects observed can basically be attributed to avoiding overheating by intentionally shooting for a much lower temperature.

There are certain catch phrases or words to look out for that are almost certainly red flags for hyperbole; “superior” is at the top of the list. Some properties that would produce a "superior" blade to some would make for a miserable blade for others. Such descriptors are subjective at best. Also note that it is indeed described as an “old” technique. If it is capable of producing “superior” results why was something as simple as lowering the forging temperature abandoned? The labor/time factor cannot explain this as we have equipment today that can squash a forging to any shape in one shot regardless of the temperature, and yet industry does not pursue this superior technique? Reality seems to be that the power of subsequent thermal treatments far outweigh any benefits seen from this concept, and the world has long since come to understand the intricacies of those heat treatments to get exactly what they want.

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It seems, for the most part, to be a case of confusing cause and effect by folks trying to explain observations in the past without the means or knowledge of what is happening during the forging process. Most of the explanations I have seen are mere assumptions that are physically inaccurate or impossible regarding the mechanisms at play which are cited. I believe the majority of the effects observed can basically be attributed to avoiding overheating by intentionally shooting for a much lower temperature.

There are certain catch phrases or words to look out for that are almost certainly red flags for hyperbole; “superior” is at the top of the list. Some properties that would produce a "superior" blade to some would make for a miserable blade for others. Such descriptors are subjective at best. Also note that it is indeed described as an “old” technique. If it is capable of producing “superior” results why was something as simple as lowering the forging temperature abandoned? The labor/time factor cannot explain this as we have equipment today that can squash a forging to any shape in one shot regardless of the temperature, and yet industry does not pursue this superior technique? Reality seems to be that the power of subsequent thermal treatments far outweigh any benefits seen from this concept, and the world has long since come to understand the intricacies of those heat treatments to get exactly what they want.

Thanks for the explanation Kevin,

So, the only benefit we get from hammering is the freedom to create the shape we want? And muscles of course...

don't forget forging is a lot more fun than grinding!

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don't forget forging is a lot more fun than grinding!

Absolutely true Matthew!! Playing with the elements is fun! But I think to understand the difference between working an alloyd "new" steel and the way it used to be with "old" techniques and the available ore.

What about this? An ABS MS gives the following description: a forged crane hook is stronger than a stock removal...

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Absolutely true Matthew!! Playing with the elements is fun! But I think to understand the difference between working an alloyd "new" steel and the way it used to be with "old" techniques and the available ore.

What about this? An ABS MS gives the following description: a forged crane hook is stronger than a stock removal...

Christophe, I address the concept of the direction flow lines in steel when forged vs. ground in my article here:

http://www.cashenblades.com/images/articles/lowdown.html

I also cover most of the other issues and misconceptions regarding forging in the same article, which I put together in order to be able to link to when having these discussion and not have to retype the information again when these discussions arise.

I do not think it is entirely true that there are no physical benefits to forging, it is just very important to understand the true causes of those effects. Many times traditionally melted steel from the mill will have segregations and inconsistencies in the carbide distribution, the multiple heating cycles at high temperature which we do in forging can be very effective in homogenizing this condition. It is just important to realize that it is the heat, not the hammer, that drives diffusion and moves the carbon/carbides around. It is also very important to note that it requires much higher temperatures to homogenize the steel in this way, low temperature cycling tends to increase carbon segregation and makes things less homogeneous. Thus, if we focus on trying to hammer the grain size finer at low temperature we miss the benefits of higher temperatures in refining carbides. Carbides are very critical to edge quality and require higher temps to manipulate while grains size is very easy to deal with after the more important operations have been done.

Great article, Kevin!

Now it's all clear about the flow lines/grains