Call for Charpy toughness samples

[Sando]

I think Michael is gonna be bored. So I mailed him some more samples to grind today.

 

[Larrin]

I think Michael is gonna be bored. So I mailed him some more samples to grind today.

Those are the S30V?

 

[Sando]

Larrin Yup. But just 8 samples. 1900, 1950, and 2000. Various tempering temps.

BTW - I see folks have various ways of doing temps. I set the oven to the desired temperature. I put the sample in when the oven 50 degrees below temp. Then it finishes ramping up and stabilizes. Then the timer starts. I hope that works out OK for everyone.

 

[P.Brewster]

I cut longer single coupons that are .120 x 1.5 x 2.75. Using a bandsaw, I cut 3 equal tines from one end leaving them connected on the other end. Use the extra 1/2 inch on the connected end to make markings/#s to keep them separate. After grinding to thickness, use an abrasive saw to trim the excess material and separate the individual coupons and grind the width. Less small pcs to handle this way. Hoss

Gotcha. At what point in this process are you heat treating?

What you describe sounds great for metal that is available in an unhardened form and reasonable thickness. In my case, I want to test a bunch of stuff that is already hardened, and up to 3x thicker than the required spec.

 

[DevinT]

Gotcha. At what point in this process are you heat treating?

What you describe sounds great for metal that is available in an unhardened form and reasonable thickness. In my case, I want to test a bunch of stuff that is already hardened, and up to 3x thicker than the required spec.

After they are cut and marked, I also drill a small hole in the marked end for a wire to enable lowering into the LN.

After HT and ground to thickness, I cut them apart and grind the edges to width.

Hoss

 

[Willie71]

Finally feeling a bit better. I’m pretty fatigued, so I’m taking a short break from cutting out the a8mod, 440b, 440c, and S90v. I’m starting with enough for 5 conditions each, plus a 6th condition in cross grain.

 

[Michael.Drinkwine]

Finally feeling a bit better. I’m pretty fatigued, so I’m taking a short break from cutting out the a8mod, 440b, 440c, and S90v. I’m starting with enough for 5 conditions each, plus a 6th condition in cross grain.

That's a lot of cutting in some tough steel... don't overdo it!

Michael

 

[Willie71]

That's a lot of cutting in some tough steel... don't overdo it!

Michael

I’m 2/3 the way done, the S90v started work hardening as my bandsaw blade is starting to dull. 440c and a8mod are cut, S90v is 1/2 done. The S90v is getting a sub critical anneal. I’ve just got a hobbyist saw, 4x6”. I’ll get a couple more blades on Monday.

 

[Ocelot85]

Do you guys want anymore 440C I might end up with some end pieces left over after this batch is cut out. It's .125 x 1.5 stock and I can surface grind it. I'm sending my knives out for HT, so I won't be able to do that. I'll mail it to whoever though.

 

[Willie71]

Do you guys want anymore 440C I might end up with some end pieces left over after this batch is cut out. It's .125 x 1.5 stock and I can surface grind it. I'm sending my knives out for HT, so I won't be able to do that. I'll mail it to whoever though.

Thank you for the offer, but I have plenty that Chuck donated for the project.

 

[Ocelot85]

Thank you for the offer, but I have plenty that Chuck donated for the project.

Thank you to all of you doing this for providing all of information for everyone to learn from.

 

[Larrin]

Do you guys want anymore 440C I might end up with some end pieces left over after this batch is cut out. It's .125 x 1.5 stock and I can surface grind it. I'm sending my knives out for HT, so I won't be able to do that. I'll mail it to whoever though.

I will take it

 

[Ocelot85]

I will take it

Ok Larrin, I'll let you know when I'm done cutting these down.

 

[Larrin]

I'm experimenting with a "log-scale" y-axis for toughness like Hitachi does. I think it might be a better representation of how the "low" toughness steels compare to those higher on the scale.

 

[rodriguez7]

I'm experimenting with a "log-scale" y-axis for toughness like Hitachi does. I think it might be a better representation of how the "low" toughness steels compare to those higher on the scale.
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Have you tested 3v and ztuff?

 

[DevinT]

Have you tested 3v and ztuff?

Check the first chart.

Hoss

 

[Larrin]

Have you tested 3v and ztuff?

I didn't make up the results.

 

[Larrin]

We now have enough Crucible steels tested to compare our results with Crucible, a check on how accurate our test is. I think the correlation looks very good.:

 

[daizee]

That scale does compress the outliers at the high end, that's for sure. Makes everything easier to see at once?

I see CPM154 at about 1/3 tougher than S35VN at 60Rc, if one extrapolates. Is that consistent with others' expectations? I've been trying to decide if my next 'fancy stainless' buy should be one or the other. My expectation based on carbon content has been that CPM154 would be tougher, but have read claims to the contrary. Kerfusing. I like data.

PSF27 is looking really good compared to A2 as a benchmark, creeping up on it well above standard D2! I'm impressed.

And all those AEB-L points are great. It's out of control, even at 63Rc!

 

[rodriguez7]

I didn't make up the results.

Ha, you never know! So it looks like it tested pretty good. And that’s at 61 rc. At 58 it should jump quite a bit according to Zapps chart. And this was all with low temper?