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sasquatch
07-14-2012, 08:25 AM
Veritas tools -(lee Valley brand, has now started doing testing on a new, (according to an email i just received,) metal they will be using in their cutting edge tools.

Labeled as PM-V11 , the PM stands for powdered metal, and is apparently faster to sharpen than A2, and holds an edge much longer.

A google search of "PM-V11" turns up some info on this.

cuemaker
07-14-2012, 10:13 AM
Powdered metals have been around for sometime and used in the knife making business for quite sometime...

Lazlo I am sure will have much more info...

Evan
07-14-2012, 10:46 AM
Powder metallurgy has been used for decades to make cutting tools such as tungsten carbide inserts.

vpt
07-14-2012, 12:16 PM
The connecting rods in my ford 7.3 diesel are powdered metal rods.

michigan doug
07-14-2012, 03:53 PM
The gun industry also fabricates small complex parts out of powdered metal quite a bit.

There were some bad opinions of said parts compared to parts machined from BILLET, but I think the use of powdered metal is just another tool. Some use it well and some don't.

Finest regards,

doug

Evan
07-15-2012, 11:19 AM
Powder Metallurgy has been used to make net shape parts such as gears since the 1970's. I have many such gears in my junk box as they were widely used by Xerox. Some types are not just extremely strong but also extremely hard. PM is excellent for short to medium run parts that are specials not available from common stock and/or have extra features that would make machining expensive. There aren't many applications where it cannot be used.

cameron
07-15-2012, 12:25 PM
More to the point, just how good is a plane blade or chisel made of PM-V11?

Lee Valley and others tout A2 as far superior to plain high carbon steel. It's interesting to note that they now sell most of their carbon blades at the same price as the A2 blades.

I'm convinced that a properly sharpened HC blade gives me a noticeably sharper edge than A2, and is faster to resharpen, effectively eliminating any advantage in wear resistance of the A2.

Something the same situation with the carbide tipped scrapers LV sells ."...stays sharp about 50 times longer than steel." I use a scraper made from a HSS machine hacksaw blade. When it's dull, I sharpen it in a few seconds on the grinder, with no worry about drawing the temper. When it's dull enough to need sharpening, it's considerably sharper than a new carbide scraper.

I wonder if PM-V11 will turn out to be the new wonder material for people who don't know sharp.

lazlo
07-15-2012, 12:52 PM
Powdered metals have been around for sometime and used in the knife making business for quite sometime...

Lazlo I am sure will have much more info...

Powdered metal in general are small particles of the parent steel that are effectively forge-welded together. The end result is higher purity (since the PM steels start from virgin stock), smaller, more homogeneous microstructure/grain size, and much smaller, more uniformly distributed carbide particles than a tool steel (in this context) that's poured from a conventional melt.

In the case of tool steel, the process is pretty neat to watch -- they fire a stream of molten tool steel at a cryogen, and the steel instantly crystallizes into an incredibly fine dust. They pack the dust in a mold, heat to the solid-state fusion temperature (substantially below the liquidus), and press under immense pressure.

Because the toughness of the steel is proportional to the grain size, the powdered metal process radically increases toughness. Which means you end up with a much tougher tool steel at the same hardness, or you can bump the hardness (a lot) and have the same toughness of a conventional tool steel of the same alloy.

In the US, Carpenter/Lasalle and Crucible are the primary powdered metal producers, with their "CPM" product line: CPM D2, 3V, M4... In Europe, Bohler-Uddeholm is the primary producer, with Elmax, Vanadis, M390's all superb knife steels.

The only downside to powdered metal tool steels (besides the cost), is they're a b!tch to forge, and forging ruins the ultra fine grain which is the whole point of powdered metals, so the vast majority of powdered metal blades are made by stock removal.

lazlo
07-15-2012, 01:06 PM
More to the point, just how good is a plane blade or chisel made of PM-V11?

Lee Valley and others tout A2 as far superior to plain high carbon steel.

Without getting into a woodworking flame war :p , I can say it's extremely unlikely that Veritas is making V11 themselves or even contracted it out. If you read my description of the powdered metal process, it's pretty involved, and there are only a handful of micro-foundries in North America and Europe making it.

It's much more likely that they're rebranding an industry-standard powdered-metal tool steel.

Uddeholm makes the Vanadis (high vanadium) series powdered metal tool steels, including V10 (equivalent to the CPM 10V), but high vandium content gives radically higher wear resistance, which means it's a b!tch to sharpen, which would be a pain for a woodworker using conventional sharpening stones. The V-series eats Japanese waterstones...

fjk
07-18-2012, 12:41 PM
Powdered metal in general are small particles of the parent steel that are effectively forge-welded together. The end result is higher purity (since the PM steels start from virgin stock), smaller, more homogeneous microstructure/grain size, and much smaller, more uniformly distributed carbide particles than a tool steel (in this context) that's poured from a conventional melt.


Neat

40 years ago I worked summers for Pitney Bowes for some R&D folks
doing PM research. I remember the micrographs from back then;
the grain/etc structure was definitely worse than non-PM stuff.
One definitely would _not_ want the PM parts then for use as
cutting blades --- you'd get the grain pattern in the cut...
THings have come a long way since then!

Btw, one place where they wanted big-honking-grains with
voids was when they made parts that were bearings.
It provided places to hold the oil.

Frank

James Kelly
10-30-2012, 01:22 PM
I would say that Lazlo has it right.
May I add something? There are Powdered Metal Parts and there are Powdered Metal tool steels, never the twain shall meet.
For example, the metal vanadium is a wonderful alloy addition to tool steel. A high vanadium steel will hold a fine edge, and not dull or wear out easily. A problem is, if the steel mill casts an ingot of steel with, say, 10% vanadium that ingot will be full of large, coarse chunks of vanadium carbide. The ingot cannot be forged or rolled into bar without crumbling, as those carbides break. So, one makes a fine tool steel powder containing that 10% vanadium. Because the powder is fine, those vanadium carbides are fine. Press the powder into a billet, sinter it, and now one has a billet which can be heated up for hot rolling into bar or plate. I would imagine it can eat up sharpening stones, but the microstructure is solid metal, not like your PM gears or gun parts.
In the early 1980's my employer stored & sheared some CPM-10V sheet for Crucible Special Metals, who developed the process. I got some scrap pieces, from which I made turning tools for a horner in Pennsylvania. Hardened & tempered them in our Lucifer box furnace, wrapped in 35% nickel tool wrap. At the time I sharpened them on the equipment we used to prepare metallographic specimens, e.g. fine alumina or diamond on wet polishing wheels. That horner is still using them, close to 30 years later. I don't know who makes Veritas' PM-11V, but the tradename implies that it contains 11% vanadium. Should be good stuff if you can sharpen it.

oldtiffie
10-30-2012, 07:46 PM
This process was known as "sinterering" such as sintered carbide for tool inserts etc. That was quite a while ago.

http://en.wikipedia.org/wiki/Sintering

http://www.google.com.au/search?q=sintering&hl=en&rlz=1R2IRFC_enAU360&prmd=imvnsb&tbm=isch&tbo=u&source=univ&sa=X&ei=j2aQUJm7Lcijiges-oD4DQ&sqi=2&ved=0CDkQsAQ&biw=1280&bih=570

http://www.google.com.au/#hl=en&sugexp=les%3B&gs_nf=3&cp=6&gs_id=m&xhr=t&q=sintering&pf=p&output=search&sclient=psy-ab&rlz=1R2IRFC_enAU360&oq=sinter&gs_l=&pbx=1&fp=1&bpcl=36601534&biw=1280&bih=570&bav=on.2,or.r_gc.r_pw.r_qf.&cad=b