Is HAP40 prone to chipping?

[Surfingringo]

I am interested in the upcoming endura sprint but I have been reading that while it will make an exceptional cutter of soft materials, it should not be hard used.

....in short, if you can use M4 without damage then you likely will be able to use HAP40 without damage.

I hope this turns out to be true as I have had good experience working with m4. It's not magic or anything but I find it to have improved performance in both edge retention and toughness compared to something like s30v.

[sal]

only 4 % Cr.

sal

[Cliff Stamp]

I just read the entire thread from Cliff's forum. I could not find a single post that talked about the performance of the steel or even one that speculated what the performance might be based on composition and ht.

This was in the first thread :

HAP40 is an odd HSS for cutlery as it is a high-cobalt HSS. Cobalt is used to significantly increase hot hardness as it delays the precipitation of secondary carbide formation and thus allows running tools hotter for longer. It makes little sense to look at those steels for cutlery in hand held knives. I suspect that these kind of choices start because either a steel is made available from the manufacturer for some reason.

Ignoring the cobalt, it is a modification of M2 to increase carbon/vanadium to increase maximum hardness and wear resistance. However if you actually want that then you would just get M4 which does the same thing, just doesn't have the Cobalt.

Speculation is conjecture without evidence. It isn't conjecture without evidence that cobalt is used in high amounts in HSS to provide high heat resistance, that is why it is added. Calling that conjecture is like calling it conjecture that chromium is in stainless steels to provide corrosion resistance. Cobalt doesn't provide superior room temperature properties hence why it isn't commonly used in significant amounts in cold work steels and hence why it isn't used in cold work applications.

As for "well if you don't have first hand experience", if someone proposed to Sal that he should make a knife out of mild steel would he actually go through all the trouble/cost of making a Mule, doing test runs, etc. . Or is it more likely he would say something like it would not have the strength/wear resistance to make a knife blade. Now if Sal said this, would everyone start tearing into him because he didn't personally use a knife in mild steel and thus he could not know from first hand experience how it would perform?

Of course not, because any reasonable person would know you can infer how a mild steel blade would perform based on its material properties and how those material properties influence the performance of a knife steel. Here is the obvious reality, if you don't believe that is true then you actually are arguing that the material properties of a steel are not what control its performance, which leaves you with what exactly - Leprechauns?

Now there are some interesting questions when you start to look at steels which are very close in comparison :

-Is the difference between HAP40 and M2 large enough to be seen without materials measurement?

-In hardening HAP40 should the upper tempering temperature be used to increase corrosion resistance and toughness at the cost of hardness/wear resistance?

-Does PM processing of HSS actually make it a better knife steel, if so in what applications under what usage?

These are questions asking very specific concerns and you are not likely to find any data on it in the literature and so answering them without evidence would be conjecture. They are also practical/interesting for users.

[spyderg]

I guess I'm one of those that likes to experience things for myself and I would guess a lot of you are that way. It's a lot different going 120 on a scooter than it is reading about going 120 on a scooter.

I know you will find it hard to believe that someone will actually lie to you to get your money. :eek: I try to be straight. The use of these odd runs of steel gives me, and you the opportunity to do some of our own testing and learning. I get to learn from my own experiences and also get to share what I learn with what you learn. I don't think we hype much, though others might. In any case, I am available for questioning.

sal

I'm excited to try it for myself too, my question is when are we going to see these available?

[can't freehand]

I am interested in the upcoming endura sprint but I have been reading that while it will make an exceptional cutter of soft materials, it should not be hard used. Can anyone speak to this? Sal, I believe you are carrying a prototype.. Any issues?

Basically, yeah, about as much as any other high carbide PM steel. HAP 40 is really just M4 with a lot of cobalt, which is only useful in very, very high speed industrial applications. In performance it's probably going to match M4, maybe better depending on how hard Spyderco runs it.

High carbide PM steels generally are tougher than non-PM high carbide steels, assuming equal blade geometry. I know my Manix's S30V is tougher than 154cm and D2, which are really weak steels.

[Surfingringo]

I just read the entire thread from Cliff's forum. I could not find a single post that talked about the performance of the steel or even one that speculated what the performance might be based on composition and ht.

This was in the first thread :

HAP40 is an odd HSS for cutlery as it is a high-cobalt HSS. Cobalt is used to significantly increase hot hardness as it delays the precipitation of secondary carbide formation and thus allows running tools hotter for longer. It makes little sense to look at those steels for cutlery in hand held knives. I suspect that these kind of choices start because either a steel is made available from the manufacturer for some reason.

Ignoring the cobalt, it is a modification of M2 to increase carbon/vanadium to increase maximum hardness and wear resistance. However if you actually want that then you would just get M4 which does the same thing, just doesn't have the Cobalt.

Speculation is conjecture without evidence. It isn't conjecture without evidence that cobalt is used in high amounts in HSS to provide high heat resistance, that is why it is added. Calling that conjecture is like calling it conjecture that chromium is in stainless steels to provide corrosion resistance. Cobalt doesn't provide superior room temperature properties hence why it isn't commonly used in significant amounts in cold work steels and hence why it isn't used in cold work applications.

As for "well if you don't have first hand experience", if someone proposed to Sal that he should make a knife out of mild steel would he actually go through all the trouble/cost of making a Mule, doing test runs, etc. . Or is it more likely he would say something like it would not have the strength/wear resistance to make a knife blade. Now if Sal said this, would everyone start tearing into him because he didn't personally use a knife in mild steel and thus he could not know from first hand experience how it would perform?

Of course not, because any reasonable person would know you can infer how a mild steel blade would perform based on its material properties and how those material properties influence the performance of a knife steel. Here is the obvious reality, if you don't believe that is true then you actually are arguing that the material properties of a steel are not what control its performance, which leaves you with what exactly - Leprechauns?

Now there are some interesting questions when you start to look at steels which are very close in comparison :

-Is the difference between HAP40 and M2 large enough to be seen without materials measurement?

-In hardening HAP40 should the upper tempering temperature be used to increase corrosion resistance and toughness at the cost of hardness/wear resistance?

-Does PM processing of HSS actually make it a better knife steel, if so in what applications under what usage?

These are questions asking very specific concerns and you are not likely to find any data on it in the literature and so answering them without evidence would be conjecture. They are also practical/interesting for users.

yes, I saw that when I read the thread. I should not have said "I could not find 1 single post"...my mistake. Aside from that though, the theme and content of the thread had little to do with hap40. It was a collective denunciation of the use of "hype" as a marketing strategy. The op pointed to the thread as the source of his information but the only reference in the thread (that I saw) to possible edge chipping was the marketing info that was copy and pasted there, which was in reference to kitchen knives. Surely you can appreciate the irony. :)

p.s. I don't think i ever mentioned the word "conjecture". Not sure if all of that was directed at me.

[animportant]

That's exactly my point, is HAP40 all hype? The second site which you didn't read before commenting on my post, spoke about not using HAP40 near bone or frozen foods due to chipping. From what I see, being similar to m4 yet having 8% of its composition be molecules that serve no aid to hand held knife use would in my mind make it obsolete to m4. I'm trying to get an idea if I should spend about $100 of my hard earned money on a knife that might not serve the purpose I want it to. If I was under the impression that this knife will easily chip, I might just spring for an orange vg10 endura instead.

[Surfingringo]

That's exactly my point, is HAP40 all hype? The second site which you didn't read before commenting on my post, spoke about not using HAP40 near bone or frozen foods due to chipping. From what I see, being similar to m4 yet having 8% of its composition be molecules that serve no aid to hand held knife use would in my mind make it obsolete to m4. I'm trying to get an idea if I should spend about $100 of my hard earned money on a knife that might not serve the purpose I want it to. If I was under the impression that this knife will easily chip, I might just spring for an orange vg10 endura instead.

I'm not sure. I will buy one as soon as they are released and let you know as soon as I have some information. :)

[tvenuto]

That's exactly my point, is HAP40 all hype? The second site which you didn't read before commenting on my post, spoke about not using HAP40 near bone or frozen foods due to chipping. From what I see, being similar to m4 yet having 8% of its composition be molecules that serve no aid to hand held knife use would in my mind make it obsolete to m4. I'm trying to get an idea if I should spend about $100 of my hard earned money on a knife that might not serve the purpose I want it to. If I was under the impression that this knife will easily chip, I might just spring for an orange vg10 endura instead.

Given that I've seen no one here make any direct performance claims I would have to say: no. It is in fact a steel similar to M4, so if that information doesn't satisfy you that it will be good for your (unspecified) uses then I would say maybe don't buy it? Or, better yet, buy it, don't use it, wait for anecdotal performance reports, and if you don't like what you see, sell it at a modest profit later. Thanks, Spyderco hype-machine!

[jabba359]

If HAP40 is a step down from M4, could anyone recommend a commercially available Japanese steel that would be closer to M4? People have been asking Sal for quite some time to make runs of Japanese models in M4. Since M4 is not a Japanese steel, that's not going to happen. Perhaps HAP40 isn't the best possible chemical makeup alternative to M4 for a knife blade, but is there a better M4 replacement coming out of Japan that's available rolled in the appropriate thickness for a set of sprint runs?

[animportant]

I think any reasonable person would want to have an idea about the performance of an item they are about to purchase. My last spydercos have been in s110v, 204p, 3v. I knew what I was getting into. I was just trying to see if I could find that info here.

[jabba359]

P.S. I don't think anyone here is hyping HAP40 to be a magical unicorn steel. They're just excited to be getting M4 (almost) in Japanese models, something we've asked for time and time again.

P.P.S. We can make guesses about performance based on chemistry, but heat treat and edge geometry will also play roles in whether it chips or not, something we won't know the answer to until Spyderco releases their knives.

[Surfingringo]

I think any reasonable person would want to have an idea about the performance of an item they are about to purchase. My last spydercos have been in s110v, 204p, 3v. I knew what I was getting into. I was just trying to see if I could find that info here.

If you check back in a few months you can. This is still a seldom used steel in knife blades. (not sure if anyone has used it in a folder before now?) There will be a lot more information available soon. If you want one of the first ones you have to accept that you are somewhat of a guinea pig. Many here enjoy that idea but it may not be for everyone.

[Nate]

...not using HAP40 near bone or frozen foods due to chipping.

Hopefully I'm not way off base, but that seems to be decent advice for knives in thin geometries and high hardness in general. That said if you haven't had issues with chipping in steels like s110v and 204p for your uses, I don't see why HAP-40 would be problematic.

I'm interested in the upcoming sprints because the color sounds cool and because I've wanted to get some M4, but I don't prefer liner locks (GB, Air) and the M4 Manix is hard to find and expensive. I think it is valid to question the selection of an alloy with a bunch of Colbalt that would not be expected to add anything performance-wise for cutlery, but if it is the "best available" for M4 like performance in Japan production, so be it.

Ironically, I've been hard pressed to identify any substantial difference in edge-holding in steels ranging from 1095 to k390 for my uses, but I still enjoy the variety, trying and learning new things, etc...

[ChrisinHove]

I think any reasonable person would want to have an idea about the performance of an item they are about to purchase. My last spydercos have been in s110v, 204p, 3v. I knew what I was getting into. I was just trying to see if I could find that info here.

If you check back in a few months you can. This is still a seldom used steel in knife blades. (not sure if anyone has used it in a folder before now?) There will be a lot more information available soon. If you want one of the first ones you have to accept that you are somewhat of a guinea pig. Many here enjoy that idea but it may not be for everyone.

Very nicely put. I also think it's truly great that Sal facilitates the easy exploration of steel qualities for those interested, by producing these niche offerings. I'm usually the worlds greatest cynic but even I slightly doubt that the sales of HAP40 knives will fund the purchase of a second private Caribbean island....

[sbaker345]

I feel somewhat obligated to point out that these are looking slightly cheaper than the non sprint zdp 189 models, So its not like you're taking a huge risk here, assuming you like zdp 189 anyways.

[can't freehand]

That's exactly my point, is HAP40 all hype? The second site which you didn't read before commenting on my post, spoke about not using HAP40 near bone or frozen foods due to chipping. From what I see, being similar to m4 yet having 8% of its composition be molecules that serve no aid to hand held knife use would in my mind make it obsolete to m4. I'm trying to get an idea if I should spend about $100 of my hard earned money on a knife that might not serve the purpose I want it to. If I was under the impression that this knife will easily chip, I might just spring for an orange vg10 endura instead.

Like I said above, VG-10 will not be any tougher than HAP-40, all things constant, and really can only be worse. Same thing with ZDP-189.

I would definitely go HAP-40 over VG-10, unless you want stainless. The wear resistance of HAP-40 is much greater.

[tvenuto]

If you check back in a few months you can. This is still a seldom used steel in knife blades. (not sure if anyone has used it in a folder before now?) There will be a lot more information available soon. If you want one of the first ones you have to accept that you are somewhat of a guinea pig. Many here enjoy that idea but it may not be for everyone.

Very nicely put. I also think it's truly great that Sal facilitates the easy exploration of steel qualities for those interested, by producing these niche offerings.

+1 on this. Spyderco spoils us with these niche offerings in uncommon or hard to work with steels. The cost is lack of history, as mentioned. I don't remember a similar cry for proof that S110V was going to be a good steel for knives.

[animportant]

Because we were able to deduce an expectation for s110v based on its predecessors and steel intent. I'm ecstatic that Spyderco gives us all these steels, that's one reason why I only buy Spydercos. I'm simply questioning this one steel. I'll get it, try it out. I'm not a super hard user, but in my mind I sort of dream of becoming a hardcore outdoors man one day, so maybe that's why I want my steel to be tough lol. If I have chipping issues, which I doubt I will, I guess I just won't use this for hard use.

[tvenuto]

I'm ecstatic that Spyderco gives us all these steels, that's one reason why I only buy Spydercos. I'm simply questioning this one steel. I'll get it, try it out. I'm not a super hard user, but in my mind I sort of dream of becoming a hardcore outdoors man one day, so maybe that's why I want my steel to be tough lol. If I have chipping issues, which I doubt I will, I guess I just won't use this for hard use.

This sounds like a very reasonable plan, I'm glad we've come to a consensus. I'll be getting it as well, and using it along with you, for whatever tasks come up. However, Sal had me at "Delica" so I would have ordered this sprint regardless of steel (I actually prefer stainless).