microserrations

[Raukodur]

I was reading a bit about dendritic steel, and wondering, are there any other steel types which develop microserrations as you sharpen them (i.e. because of carbide crystals or a combination of harder and softer steels)? The current pattern welded damascus blades, do they work in this way?

[dks]

Some steels, D2 comes to mind, get a "toothy" edge, from the beginning.

[Raukodur]

Thanks for the info, doing some quick reading, it seems there is a general consensus about D2 being quite good in this regard.

But the other very widely made remark is that it is a nightmare to sharpen, which puts me off considering a D2 knife.

Any other steels?

[dks]

I do not find D2 any different to sharpen compared to most 440 type, decently heat treated steels. I did find that it is a lot easier to sharpen on a diamond stone than with my Lansky system.

[Raukodur]

Interesting. Seems Queen make slipjoints using D2, any other companies?

What about modern damascus, given the use of two steels of differing hardness, does that form microserrations upon sharpening?

[jzmtl]

I very much suspect the "whatever steel is hard to sharpen" crowd is using the wrong stone, i.e. arkansas stone on s30v. Nothing is hard to sharpen with a appropriate grit diamond stone.

Damascus (modern) by definition need two type of steels, one that's easy to corrode and one isn't, and at least one of them will be very badly suited for cutlery steel. The high performance knives only use damascus in laminated blade as clad, and a real cutlery steel as core.

[Raukodur]

Can anyone suggest a compact, lightweight, D2 steel, UK legal folder, if there is such a thing?

[dks]

queen has a few. Check tsaknives for ideas.

[sticktodrum]

Sharpening media does have a lot to do with the "ease" of sharpening when it comes to a higher wear steel. I've found that higher wear steals aren't any more difficult to sharpen, they only take a bit longer. Using diamond media will mitigate and issues some may have with a steel wearing their sharpener and in many cases shorten the process.

What was already said about Damascus blades is more or less true, however there are exceptions like Damasteel and some of the stuff Alabama Damascus makes. I wouldn't, however, choose a Damascus steel blade for the sake of finding microserrations.

The texture of an edge right after sharpening has a bit more to do with the sharpening work than the steel, provided you're sharpening properly. A steel like D2 can take a very refined edge without any sign of toothiness or jaggedness to the apex. The same can be said for high Vanadium steels like S30V, S90V, 110V, etc. Those steels are necessarily made using powdered metal processes to keep their grain fine, as the carbides that form are fairly large and would cause an unevenly course grain structure in the finished product.

When the edge of a carbide-rich steel begins to wear, the smoother matrix gives out around the carbides and results in a more jagged edge with semblances of microserrations. S30V has become a bit of a standard for folding knives because of its ability to keep cutting after the finer edge has worn. The edge retention of a high Vanadium steel puts a lot of its value in the carbide content to allow more cutting beyond the point that one would still feel the edge as razor sharp. I like to think of it as chunky peanut butter, and the carbides are the chunks that become visible after the creamy steel matrix has been worn away.

A nightmare to sharpen D2 is a bit of a stretch. I thought that Elmax was a pain to sharpen because it took forever. Then I sharpened S110V, only at a hardness of 59HRC. Long came Carpenter's B75P at about 61HRC, and S110V no longer seemed daunting. D2 would be a welcome steel to sharpen, and sometimes I need to be very careful about sharpening a SAK because the steel isn't as robust as what I've gotten used to.

I've got a couple of Kershaws in CPM-D2, and that stuff is great. A bit tougher than regular D2, and slightly easier to get a very refined edge, since the powdered metal version has a finer grain structure. Good stuff.

It's hard to go wrong with D2, but I wouldn't discount a premium Vanadium steel like S30V either.

[Raukodur]

Thanks for the very useful information 

So I am currently interested in steels that have these carbides which will produce a microserrated edge when sharpened to a degree.

Apart from D2, which other steels fit that specification?

[David]

Spyderco has been making a number of knives in Carpenter CTS-XHP. Many consider it a stainless D2 type steel. I`ve had no problems sharpening any of the three knifes I have made of CTS-XHP.     

[David]

Here is a link to Spydercos steel page.

[Raukodur]

Thanks for the suggestion  but doing a bit of prelim reading, I have found mention that it is a powdered steel, which means it would lack the larger carbides necessary to form microserrations on sharpening/use. Or am I mistaken?

[David]

Yes, it is a 2nd generation powered steel if I remember correctly.

[jekostas]

Thanks for the very useful information 

So I am currently interested in steels that have these carbides which will produce a microserrated edge when sharpened to a degree.

Apart from D2, which other steels fit that specification?

S30V

[sticktodrum]

Thanks for the suggestion  but doing a bit of prelim reading, I have found mention that it is a powdered steel, which means it would lack the larger carbides necessary to form microserrations on sharpening/use. Or am I mistaken?

Slightly mistaken. Some steel mixtures require the use of powdered metal technology because their ingredients wouldn't properly form a homogeneous billet with a common melt. S30V is a powdered steel also, and all the high Vanadium steels from Crucible are also.

They still form carbides in the solution, so you'll have that property if you have any S30V blade. I haven't had much experience with XHP, but it looks pretty damn good on paper.

[Raukodur]

Right, but don't you need carbides of a certain size to get the microserration effect? I would have thought if they are too small then the effect would be negligible. Do people find their S30V knives to have this effect? It's not something I have managed to find many comments on, apart from in one forum where they were commenting that if you don't put a mirror finish on the blade edge, someone people complain about microchips, which they put down to a microserration edge on a brittle metal.

[sticktodrum]

I'm uncertain of the required size, however S30V is an older steel with a very solid track record for edge retention. It gained that reputation because of its ability to cut after the initial edge has started to wear. That Vanadium carbide structure is the main component behind that. The talk of microserrations is a bit new, and is more attributed to the coarseness of the grit left at the edge. The carbides in a steel that continue to cut a material isn't usually referred to as that because when looking at the edge with a microscope you're likely to see what looks like a jagged and damaged edge.

It's not as if one can particularly control the size of carbides, as they form at the propensity of the respective elements in the solution. Using powdered metal processes to produce the billet mitigates the elements' tendency to form even larger carbides that would compromise the homogeneous grain of the steel. The side effect of this is that the steel is also a bit tougher.

There are a couple of aspects to keep in mind with steel, especially when talking about more advanced mixtures and their sharpness. The new edge that one may put on a knife is what some would call a fine edge. It's the primary apex of the blade, and is what gives a knife its razor sharpness. A harder steel will retain that fine edge longer, as will a steel that is more wear resistant. For example, Elmax is a very tough steel and that toughness will give it the ability to reduce fracture. The fact that it's a powdered steel is part of that. Given its toughness, it can be tempered to a higher hardness and still resist impact damage at the edge. The toughness of that steel will mitigate its brittleness so that it can retain a fine edge longer. Unfortunately, the steel doesn't have the kind of high Vanadium mix that say, S30V would, so once that fine edge is worn, it would actually become dull. A high Vanadium steel would still retain cutting ability after the fine edge is worn due to the grain structure of the steel. The jagged damaged edge would retain a working edge at the macro level.

This is assuming that the heat treat, grind, and edge are all identical. That is a bit harder to control in testing, but I'm just giving you extrapolations of what the steel properties are on paper.

So, my advice is to not hold on to the word microserration so much, as it's used loosely these days and sometimes a bit incorrectly. Admittedly, by myself as well.

Micro chipping isn't what I'd call serrations though, as that is just fracturing of the steel at the edge. That could happen during sharpening, or during use.

Mirror polishing for me is a point of diminishing returns, as it doesn't do much more for me or the steel beyond a level of work that can get a steel working properly. But either way, I have yet to know someone who has been disappointed with the performance of an S30V or D2 blade.

[Raukodur]

very sensible advice.

I was reading a thread on a different knife oriented forum, and there was a lot of discussion about different steels, and someone made mention that a relatively soft steel had outlasted another steel which is considered much better when he was doing his daily fishing work involving quite a lot of cutting. This resulted in a lot of name calling, and other forum members basically saying they didn't believe him, etc etc.

Then this one guy stepped in, and said that while that may not be a basis for saying that one steel is better than another, he wouldn't have a problem believing the story. Because there are so many factors involved in determining a knifes cutting ability and edge retention, only one of which is the steel; e.g. blade grind, thickness, edge thickness, bevel edge. One of the points he stressed more than other was blade width, in that a thinner blade will cut more effectively than a thicker blade even if the thicker blade is made from a 'better' steel.

And with regards to steel, a point which came up again and again was that the only people who really need a steel which has better than average edge retention are those who use their knives in one sitting (e.g. a job which involves lots of cutting), where if the knife becomes blunt enough during that episode to hamper its cutting ability, it would require resharpening which would be a pain/waste of time/not feasible. Which means for the vast majority of us, the negative of a steel that is harder to sharpen outweighs the benefit of the extra edge retention, because during our normal use it would make no difference to us, a softer steel would be able to retain enough of an edge.

Which means what? From that what I take away is that for an average user, having a knife which has a very thin blade, made from a relatively soft/medium hardness steel, would give superior cutting ability, and allow for quick sharpening. And because it would be quite cheap, and quite tough given the softer steel, it could be used and abused and even if it does fail (which it is unlikely to do), it can be easily replaced.

[sticktodrum]

Very true. Although, I will say that more premium steels offer a bit more longevity in a blade. Of course, that too depends on use. Something like S30V or my favorite CPM-154 offers generally better edge retention and toughness than something like a 440 series. Depending on someone's sharpening practices, one material would be able to withstand more stropping and fine touch ups before you'd ever need to actually sharpen it back up to renew the bevel. That can preserve more material and not wear out a blade as quickly.

For most enthusiasts, that scenario isn't too important because each knife doesn't wear too much when there's a rotation of tools. However, I really only use about three knives, one of which much much more than any other. That knife is an S30V Kershaw Skyline, and it retains usefulness noticeably longer. It's also a limited edition, so replacing it would be difficult.

That's a pretty specific example, but I just want to show where I come from on my thought. I've found a lot of discussion on places like BladeForums too often gets ridiculously childish and angry. That's why I don't frequent that forum anymore. I prefer it here where the attitude is much more amicable and geared toward sharing ideas.

[Raukodur]

Indeed!

For me, after having done a lot of searching and researching, I've settled on a Wenger Patriot. Its UK legal, its VERY light and fits on my keyring nicely, and its got very thin blades, made of good quality steel which is very easy to resharpen even if it doesn't have the best edge retention. And it cost me something like £16, although I hardly end up needing to use it, I would be ready to use and abuse it since I fancy testing it to see what it can tolerate, and it would very easy to replace.

[Raukodur]

Resurrecting this thread to ask a question about damascus steel blades:

Do the two steels have different hardness? If so, when you sharpen or even use the blade, I would assume the softer steel within the pattern would wear away quicker than the harder steel; and if so, does that give damascus blades a toothy feel?

[Raukodur]

No-one have any ideas on this?

[dks]

Victorinox gives just one hardess rating for the whole blade for their damascus knives. They use SS.