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Powdered Metal vs HssCo
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As in you're manufacturing endmills out of P/M? If you're looking at P/M steel endmills, I'm guessing you're looking for something like T15 or a grade similar to CPM-121?
If it's T15 (I'll assume we're talking Fully Dense material), pay particular attention to carbide size. The advantage of the P/M process is that you can control the grain growth and also get a finer dispersion of carbides. A good fully dense T15 will have finer/smaller carbides than the pooling or chunkier carbides you'll see in wrought steel. This works well for wear, and is also nicer for grinding. You likely won't have the same level of surface cracking during grinding as you will be ripping out smaller carbides with your wheel vs. chunkier ones.
Manufacturing...that's going to be a little different, especially if you're going to ask someone to mold in the flutes (w/o using MIM).
If it's T15 (I'll assume we're talking Fully Dense material), pay particular attention to carbide size. The advantage of the P/M process is that you can control the grain growth and also get a finer dispersion of carbides. A good fully dense T15 will have finer/smaller carbides than the pooling or chunkier carbides you'll see in wrought steel. This works well for wear, and is also nicer for grinding. You likely won't have the same level of surface cracking during grinding as you will be ripping out smaller carbides with your wheel vs. chunkier ones.
Manufacturing...that's going to be a little different, especially if you're going to ask someone to mold in the flutes (w/o using MIM).
Sorry, pressed send by accident...
Average hardness? I can get my fully dense T15 to 65-67 HRc. Although with the vacuum process getting over 66.5 is a crapshoot sometimes.
Sounds like you're looking for barstock CPM grade steel. Depending on the grade, that might be more difficult to find. If you're looking for someone to mold blanks for you, that might be easier to find...you just have to find a P/M company with fully dense capabilities with experience in tool steels. That's a bit harder to find.
Average hardness? I can get my fully dense T15 to 65-67 HRc. Although with the vacuum process getting over 66.5 is a crapshoot sometimes.
Sounds like you're looking for barstock CPM grade steel. Depending on the grade, that might be more difficult to find. If you're looking for someone to mold blanks for you, that might be easier to find...you just have to find a P/M company with fully dense capabilities with experience in tool steels. That's a bit harder to find.
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Thanks for the input guys!
We are a manufacturer that machines alot of 15-5SS and have switched to PM cutters because they do perform better. We like to justify purchases by gathering solid technical data for making decisions not sales claims so I am trying to compare HSSCo vs PM vs PMCo substates before we make a large purchase.
Is the difference between Powdered Metal & Powdered Cobalt or is it just a nominclature thing because some do not claim cobalt content?
Are all materials simalar, does T15 have cobalt content?
Niagara - Particle Metal, 8% cobalt
Fastcut - T-15
Cleveland - Powdered Metal, 8% Cobalt
Hanita - Powdered Metal
PCT - PM30 w/ 8.5% Co & PM60 w/10.5% Co
We are a manufacturer that machines alot of 15-5SS and have switched to PM cutters because they do perform better. We like to justify purchases by gathering solid technical data for making decisions not sales claims so I am trying to compare HSSCo vs PM vs PMCo substates before we make a large purchase.
Is the difference between Powdered Metal & Powdered Cobalt or is it just a nominclature thing because some do not claim cobalt content?
Are all materials simalar, does T15 have cobalt content?
Niagara - Particle Metal, 8% cobalt
Fastcut - T-15
Cleveland - Powdered Metal, 8% Cobalt
Hanita - Powdered Metal
PCT - PM30 w/ 8.5% Co & PM60 w/10.5% Co
For things like carbide tooling, cobalt acts as a binder during liquid-phase sintering. It also is used in liquid-phase sintered materials like T15 (although mine runs around 5%). Powdered cobalt is either blended into the powder mix for the material or pre-alloyed in the melt prior to atomization.
Honestly, you need to read through the P/M process explanation on the MPIF website ( It will explain how powder is made, blended, different manners of compaction, different styles of sintering, etc. This may give you some background for future questions. The mix all depends on how your material is being consolidated. Is the material HIP'ed, CIP'ed, sintered in liquid-phase to be wrought, etc.? The process used, blend amounts, etc., will affect the end product in different manners.
The easiest comparison I guess you could make would be to look at standard wrought material data sheets for the cobalt percentages (I'm guessing they'll be running around 5% for T15). Then look at the cutters with the higher cobalt content. If I had to guess, you might get a little better wear out of the lower Co content cutters with better toughness/chip resistance out of the higher Co content cutters. Wrought stainless is gummy, so you might also have some cold weld issues with the higher binder content cutters. No factual data to back that statement up, just a gut feeling.
Looking at the material grades you've listed, make sure you're comparing apples to apples. If your purchasing M2 cutters and T15 cutters (both P/M), they're going to react differently with different materials and applications. What's good for one application may not be optimal for the other.
Honestly, you need to read through the P/M process explanation on the MPIF website ( It will explain how powder is made, blended, different manners of compaction, different styles of sintering, etc. This may give you some background for future questions. The mix all depends on how your material is being consolidated. Is the material HIP'ed, CIP'ed, sintered in liquid-phase to be wrought, etc.? The process used, blend amounts, etc., will affect the end product in different manners.
The easiest comparison I guess you could make would be to look at standard wrought material data sheets for the cobalt percentages (I'm guessing they'll be running around 5% for T15). Then look at the cutters with the higher cobalt content. If I had to guess, you might get a little better wear out of the lower Co content cutters with better toughness/chip resistance out of the higher Co content cutters. Wrought stainless is gummy, so you might also have some cold weld issues with the higher binder content cutters. No factual data to back that statement up, just a gut feeling.
Looking at the material grades you've listed, make sure you're comparing apples to apples. If your purchasing M2 cutters and T15 cutters (both P/M), they're going to react differently with different materials and applications. What's good for one application may not be optimal for the other.
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