Blade Material and Forging

[Guerre]

I am currently trying to put together a small project studying the manufacture and durability of blades (focusing on foil blades). The intent is to create a spreadsheet or database detailing stiffness (in a numerical value), force needed to cause a buckling break in the blade and general longevity of the blade (via a derivation of required forces for permenant deformation).
I am assuming that few forges would produce the information i'm looking for because it would give away too much about their processes. The most important pieces of information are the Young's Modulus of Elasticity (E), the yield strength (Sy) and ultimate strength (Su). For those not familiar with the terminology these three factors all contribute to how your blade bends, how much force it takes to cause a permenant bend and how much force it takes to cause deformations in the blade leading to breakage in the material. Over the next year i will have access to some machinery which will allow me to perform tensile tests on some blades, in an attempt to find this information. If anyone else has done similar research or has information (even if its dated) on forging processes (which may not actually involve forging), or can direct me to a site or an individual that may have some of this information i would appreciate it.

[CvilleFencer]

My only suggestion would be to contact Alex or Barry Paul at LP. They produce most of their own blades in house. They do a great deal of testing of their own and competitors blades and I am sure they have a great deal of data not just on their brands but others. Also they are very knowledgeable about testing and the engineering aspects of fencing gear in general, even having helped some other forges establish their procedures IIRC. I am not sure how much of their actual "recipes" or processes they can divulge, but I am sure they would be a very valuable resource for you.

[Alex_Paul]

You beat me to it Cville!

We test a lot of blades but on blades we buy in we only test durability in terms of bending cycles as per the FIE test.

We may be able to help / send samples for testing. e mail alex (at) leonpaul.com I am off to the JO's now so I may take a week to get back to you.

Alex

[SJCFU#2]

Have you tried looking at Appendix A to the Material Rules for mechanical characteristics?

This sounds like an interesting study. The big problem I see will be difficulty achieving any consistent results if data is collected based solely on blades that are used in actual fencing. It seems like the varying number of beats, misapplied bends, and other flaw-inducing events any individual blade might experience would sufficiently alter the results to prevent drawing anything more than the most general of conclusions. Of course if your study is strictly limited to testing of brand new blades under laboratory conditions then you will be able to get more consistent results, but then the question will how well do these results compare with blades that are actually being used.

[jjefferies]

Originally Posted by SJCFU#2

Of course if your study is strictly limited to testing of brand new blades under laboratory conditions then you will be able to get more consistent results, but then the question will how well do these results compare with blades that are actually being used.

Such a study would almost like be statistical in nature. So how many samples can you obtain of new weapons? Old i.e. broken weapons, you can have as many as you want. But then how to perform meaningful tests.

Of course if you can do it we would all be interested in the results particularly any statistics determined.

[Guerre]

The thing about it is that there realy isnt going to be alot of difference in the data. All three values are determined by the process and the material make up. Changing the recipe for the steel one way or another just a tiny bit wont realy make that much of a difference in terms of those values. The current testing is bending and how many cycles the blades can withstand, im trying to look at it from the viewpoint of re-setting yield strength (with every permenant bend that section requires more force to cause another permenant bend). This has little to do with the way someone actually hits or with what kind of hits, the whole point is to find out just how much force or repeated force it takes to deform the blade to the point where it is no longer functioning or breaks. In any case thanks for the replies.

There should be almost no variability between blades in the same batch in these terms. I plan to test the forte of the blade since minor imperfections in the steel will have a smaller effect with a larger cross-sectional area. Those imperfections are the reason that two blades from the same batch could have a massive difference in lifespan.

[Pescados666]

Originally Posted by Alex_Paul

You beat me to it Cville!

We test a lot of blades but on blades we buy in we only test durability in terms of bending cycles as per the FIE test.

We may be able to help / send samples for testing. e mail alex (at) leonpaul.com I am off to the JO's now so I may take a week to get back to you.

Alex

Free samples? If so I could do a few of my own tests...