M390 vs. M4 vs. s30v

[Ankerson]

Jim I'm guessing here but my feeling is that they are changing over purely to eliminate concerns about S30V chipping. I have personally not experienced this chipping but I guess if the rumours are persistent enough it can become a real problem.... so I guess with that 10 - 20% increase in toughness, or whatever it is, they can say presumably kiss any chipping issues (real or imagined) goodbye and put that boogeyman to bed.

I haven't ever had S30V chip on me either and that's at 59 HRC and higher.

 

[JNewell]

Correct me if I'm wrong, but when Crucible gives a figure for "toughness" it has nothing to do with edge retention. It has to do with resistance to lateral force...in other words, basically (for our purposes) resistance to chipping when edge-prying.

I like them all - I just don't use knives hard enough to be able to clearly see a lot of the differences. I'm also not great at sharpening, so I constantly try to touch up my blades so they do not get dull.

I like CRK S30V - I have an Umnumzaan and Sebenza and the steel holds up well for what I use my knives for.

CRK is switching over to S35V over the next 12 months - and it is reported that it might offer 15-20% more toughness that S30V - but I probably wouldn't notice the difference with my usage.

Some argue that the steel type is only one part of the equation - grind, shape and heat treat also seem to play a role in the overall performance of a knife blade.

I use the new steels as part of the justification to myself as to why I need to buy another knife.

Whoops, looks like dwarthog already got that...

Hmmm, I must be missing something when reading that data sheet.

From the first page.

Quote:
Substituting niobium carbides for some of the
vanadium carbides makes CPM S35VN about 15-20% tougher
than CPM S30V without any loss of wear resistance. CPM S35VN’s
improved toughness gives it better resistance to edge chipping.​

 

[Ankerson]

Correct me if I'm wrong, but when Crucible gives a figure for "toughness" it has nothing to do with edge retention. It has to do with resistance to lateral force...in other words, basically (for our purposes) resistance to chipping when edge-prying.

Yeah I know exactly what they are talking about. :thumbup:

 

[JNewell]

Yeah I know exactly what they are talking about. :thumbup:

I knew you knew...

 

[Toyz]

I stand behind my original post - not that I'm smart - just good at copying.

 

[hardheart]

Crucible wanted to offer something that was a little easier to finish/polish, while still maintaining the wear resistance of S30V. Toughness was probably actually secondary, a result of the additional carbide former reducing average carbide size. So this is supposed to be an overall improvement I think - wear resistance equal to S30V & higher than CPM154, tougher greater than both, and finishes more like CPM154 and easier than S30V.

 

[Gator97]

Correct me if I'm wrong, but when Crucible gives a figure for "toughness" it has nothing to do with edge retention. It has to do with resistance to lateral force...in other words, basically (for our purposes) resistance to chipping when edge-prying.

It doesn't have to be prying, depending on the user experience level and hand steadyness, plus material being cut, we all apply various lateral loads to the edge, so do the irregularities in the mediums. Thiner edge == more pronounced effect.
So, it's quite relevant to edge holding

 

[Big Mike]

Even if it might be 10-15% difference from S30V it won't matter one bit if the production manufactors aren't going to take advantage of the added toughness.

S30V is already very tough when run at around 58 HRC so running S35VN at the same hardness won't really make any noticable difference for most of the users. So the point of changing makes no since at all unless they are going to make choppers out of it. For folders I don't see the point at all unless they are going to raise the HRC to take advanage of it, they might as well stick with S30V if that is what they are going to do.

The steels are just too close to each other and if the advange of S35VN is that they solved the chipping issues of S30V when run around 60 HRC then they could run it at a higher HRC than S30V, if they don't then it's a waste.

Agreed.

But one of the main reasons makers might go with the S35VN is it's ease of grinding and finishing when compared with S30V.




Big Mike

 

[Ankerson]

Crucible wanted to offer something that was a little easier to finish/polish, while still maintaining the wear resistance of S30V. Toughness was probably actually secondary, a result of the additional carbide former reducing average carbide size. So this is supposed to be an overall improvement I think - wear resistance equal to S30V & higher than CPM154, tougher greater than both, and finishes more like CPM154 and easier than S30V.

Now that makes since. :thumbup:

I guess we will see how it works in the end.

 

[Noctis3880]

Gonna have to agree with Ankerson here. I've never had a problem with S30V regarding toughness. If anything, the edge would roll before it ever chipped. And while CPM154 seems to be the better performer at Rc62, I suspect S30V would outperform it if both were at the same hardness. It's hard to gain anymore benefits from S35VN unless the steel is pushed harder. From a user perspective anyway. I have no idea how the thing heat treats.

 

[Ankerson]

Gonna have to agree with Ankerson here. I've never had a problem with S30V regarding toughness. If anything, the edge would roll before it ever chipped. And while CPM154 seems to be the better performer at Rc62, I suspect S30V would outperform it if both were at the same hardness. It's hard to gain anymore benefits from S35VN unless the steel is pushed harder. From a user perspective anyway. I have no idea how the thing heat treats.

Yeah I fail to see how the end users will even notice the difference between S30V and S35VN in the same model knife at 58-59 HRC. I doubt they could tell the difference if the blades aren't marked..

Push S35VN to 60-61 HRC taking advantage of the increased toughness and we might have something here. :thumbup:

I am pointing this out because the supposed issues with S30V are around 60 HRC so S35VN should be able to handle 60-61 HRC from what they are saying.

That is if it's really that much tougher that is.....

And I am EDCing a Spyderco Military in S30V at tested 60 HRC almost 100% of the time these days and it's rocking right along with no issues.

 

[knarfeng]

OK....are m4 and m390 that much more superior to s30v?? How?? Thanks. And let me throw Benchmade's 1095 steel into the mix. How does it compare to the other 3 steels? Many really good fixed blades come in 1095. Why? What does it offer. Chris Reeve has a good reputation. His fixed blades come in S30V. Why not one of the others if they are superior?

Both have vastly superior edge retention.
In the chart below, 1095 would appear to have the same edge retention as AUS8.

The chart is based on my testing, details are here:
http://www.bladeforums.com/forums/showthread.php?t=792540

As for CRK, far be it from me to tell ANY knife maker what alloy he should be using, especially one with the experience and abilities of Chris Reeve.

 

[elkpro1]

I used s30v for years in the field on tough work like skinning and deboning animals like elk on the ground. I thought at the time it was the best steel ihad used exept for 440v which chipped badly . Now i have gone back to tool steels with m4 my favorite becuase it cuts like 1095 but is the easiest thing to maintain a badass guilt grabby type cutting edge i have ever seen . No matter what steel you use you touch it up in the field in my line of work and m4 takes about 30 seconds 3 or 4 times on one elk and other steels like 1095 require constant miantenance , even a2 and d2 take alot of time to touch up or just plain resharpen . S90v is awesome but if you hit a rock or something it takes awhile to get it that sharp again , m4 on the other hand sharpens easy anh like s90v really cuts when dull .

 

[nozh2002]

OK....are m4 and m390 that much more superior to s30v?? How?? Thanks. And let me throw Benchmade's 1095 steel into the mix. How does it compare to the other 3 steels? Many really good fixed blades come in 1095. Why? What does it offer. Chris Reeve has a good reputation. His fixed blades come in S30V. Why not one of the others if they are superior?

All those steels are not on top of performance list. CPM M4 on 10th place (and I am talking about Spyderco Mule, I think BM most likely will show lower results)

I would rate them this way:

1. CPM M4 is best Crucible performer
2. M390 is best Benchmade performer I see
3. S30V entry level PM steel with average results (actually CPM S30V heat treated by Buck is little better then M390 by BM, but Buck usually do heat treatment much better then others, so I expect M390 to be better then average CPM S30V).

1095 heat treated by pro - like Jody Muller are better then any of that, but I do not know about BM heat treatment which is usually not the best.

Here my test results:

http://playground.sun.com/~vasya/Manila-Rope-Results.html

Thanks, Vassili.

 

[The Mastiff]

1095 heat treated by pro - like Jody Muller are better then any of that, but I do not know about BM heat treatment which is usually not the best.

Better in your opinion maybe. It should be apparent there are lots of very knowledgeable people around here that don't agree with your methods or results.

Maybe you should just stick with something like "better in my opinion", or " I like it better".