Annealing will have a much bigger effect on hysteresis and Hc than Bsat. Can't give you any hard numbers. Generally, the anneal is done after machining. It's not nearly as expensive as the material itself.

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since it was hot rolled, I guess the material is bar/rod form, but not strip form? if is not strip, if or not H2 anneal doensot matter much, a vacuum or Ar anneal would give you close results as H2 anneal. Also, the material will probably have an ordered structure after hot rolled, which is beneficial to magnetics. therefore,use as it could be acceptable if you donot put much of cold work afterwards.

Anneal wonot change your Bs, what changed are Hc and core losses, if your applcaitions are DC, and your design can suppply a sufficient high field (current) to saturate the magnet, no much effect after anneal. but then Hyperco 50 is good enough. Hyperco 50A is more pure for a lower Hc and lower core losses.

It really depends on your applicaitons to decide which way to go.

dgallup, do you know of any sources and what price they would charge for the magnetic anneal? Bob Rossi told me he heard it was about $1200 for the dry H2 and roughly $700 or so for a vacuum anneal, haven't heard about argon. One thing I never understood, isn't it rather dangerous to be using hydrogen especially at elevated temperatures?

Magben, our material is a 5/8th diameter hot rolled bar, which will be machined down to around 0.375. Bob also gave us some very good machining advice to minimize adversely affecting the magnetic properties. Our application is for a non-repetitively pulsed solenoid, a high Bsat value is our main concern.

Does anyone know just how much better than Hiperco 50A is supposed to be over pure iron, at least for DC applications?

If you design a solenoid/solenoid valve what is the ferromagnetic material of the rest solenoid parts. If you plan to use some sort of iron or low carbon steel for the other parts then you will have to make them 25% thicker to exploit the Hiperco 50A properties. Leaving you with less space for the coil and the plunger. In my experience you may find a combination of larger diameter plunger, coil wire, number of turns, and thinner parts of the solenoid and make all parts of the solenoid from iron or low carbon steel. If you can give the:

1. Available space for the solenoid
2. Supply voltage (hopefully, DC)
3. Maximum current available
4. Force needed from the solenoid and from what distance.
5. Time from command to full travel of the plunger (Electrical plus mechanical time)

Any other relevant info I can make a quick check if it is feasible.

Most heat treatments charge by the furnace load. So if you can get thousands of parts in the furnace that $1200 per load is less than $.5 per part, maybe a lot less. If you only have one part maybe you can piggyback with someones parts. H2 is not dangerous in the absence of oxygen. Very dangerous in combination with oxygen. So it takes proper furnace controls to ensure the two don't mix.

If you are only looking for max saturation flux density the anneal will make very little difference. It will make a big difference if you are trying to operate the solenoid at say 200 Hz or above.

This material should saturate at ~2.4 T. Pure iron will saturate at ~2.15 T. The pull force is a function of B^2 so the difference is ~25% more pull force with the 50% cobalt. See the attachment for BH curves of many common magnetic materials

As israelkk said, you can usually accomplish the same thing with pure iron or other materials unless you are severely space or time response constrained. You should look into a magnetic FEA program like Infolytica's MagNet or the freeware FEMM. FEMM only does 2D stead state (last time I checked) but sounds like it may be sufficient for your purposes.

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Does not Scientific Alloys have anneal furnace? I happened to talk with Bob's father, Jim Rossi, and know that they are dealing with all kinds of soft magnetic alloys.
You may also try Thomson Lamination at NJ and Wingard at MD, both of which are purchasing Hyperco 50 from Carpenter and have the furnaces and even the recipes for H2 anneal.