Titanium dive knife 60 to 65 hrc?

Rockwelledge75 said:
Titanium dive knife manufacture claims 60 to 65 hrc

http://www.oceanmaster.com/KnivesFeatures.htm

thoughts?
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"As the name states, Custom-Formulated Beta Titanium knives are made with a special formula--not built with the less expensive, off-the shelf, softer 6Al4V titanium. The Ocean Master material produces a non-brittle, highly abrasion resistant, and high Rockwell hardness titanium knife. These combined qualities have never been achieved in any other titanium knife. The Custom-Formulated Beta Titanium is indeed the knife for you.

Have the best.

Be one of the few to own one of these knives. If you want a knife that is currently being used by the U.S. Army, you've come to the right place. Some owners go so far as to having their name placed on the knife through the Ocean Master Engraving Department.

You won't just be owing a knife, you'll have a treasure trove of secrets. The formula has never been patented."

Sounds like marketing hype...super secret beta-Ti formula that's never been patented😂
 
WValtakis said:
"As the name states, Custom-Formulated Beta Titanium knives are made with a special formula--not built with the less expensive, off-the shelf, softer 6Al4V titanium. The Ocean Master material produces a non-brittle, highly abrasion resistant, and high Rockwell hardness titanium knife. These combined qualities have never been achieved in any other titanium knife. The Custom-Formulated Beta Titanium is indeed the knife for you.

Have the best.

Be one of the few to own one of these knives. If you want a knife that is currently being used by the U.S. Army, you've come to the right place. Some owners go so far as to having their name placed on the knife through the Ocean Master Engraving Department.

You won't just be owing a knife, you'll have a treasure trove of secrets. The formula has never been patented."

Sounds like marketing hype...super secret beta-Ti formula that's never been patented😂
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Could be, I've had fairly long discussions on here with Macha who's basically this forums resident titanium expert and he said while certain titanium alloys can be heat treated to low to mid 60s they're almost always brittle at that hardness and nearly impossible to put a good edge on because the grain structure gets really messed up. So yea highly suspicious that this knife is both hard and tough and if this alloy was so amazing why not patent it hmmmm 🤔
 
tokerblue said:
Get a Spyderco Salt. Or a Magnacut knife. Possibly a Magnacut Salt in the near future?
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Excellent choice yes, it can reach RC 64 to 65, is fairly tough and the most stainless out of all stainless steels capable of reaching those hardness levels.

I think titanium might be more corrosion resistant still but magnacut has such high stain resistance that even in an ocean environment it should be fine provided you clean it off well after you get out of the water.
 
Following, no idea you could get that hardness out of titanium. Anyone know what the heat treat is ?
 
I don't believe it unless the bought a master heat of Titanium @50k lbs

But still going to call.... BS
 
These things have been around a long time. I destructively tested one of them about 7 years ago, including breaking it in half. I found it to have enormous grain, indicative of being way overheated in what I assume is an attempt to drive up the HRc numbers. The knife was not easy to break, it was surprisingly strong, and snapped viciously when it yielded. The edge itself was not tough and it was really easy to notch it deeply with a steel blade or otherwise damage it with impact. It didn't hold a fine edge very well despite obviously having been hardened, I suspect because of the poor grain structure and other bad things that happen when titanium alloys are overheated.

The super-secret custom-formulated titanium alloy thing is just pure nonsense. Back when I looked into these ti diving knives, I found that they're all made in China despite what a brand may claim, probably at the same plant, which is why all the various brand names of these ti diving knives look the same. You can get pallets of these things from Alibaba for like $30 a unit or less.

I've heard some people say their example works well, and I suspect they're not consistently heat-treated and some are better than others, also likely due to the irregularities in a lot of Chinese titanium alloys made from recycled ti. I know there's excellent ti alloy made there for other purposes than just basic consumer products, such as the defense and aerospace industries. Making the good stuff is expensive. Making a good blade out of it is difficult and easy to screw up.

As a diving knife, for prying, poking, and chipping at things on the sea floor, spearfishing, stabbing an attacking shark or maybe cutting a cord, it would be ok. Most non-knife people probably wouldn't even notice anything was off. Frankly, I'd rather just have a Magnacut knife or anti-shark sword for those tasks. But not a shiny one because then I'd get bit by a barracuda. XD

I don't like these knives simply because they generate a lot of additional BS concerning titanium, which constantly surrounds the metal like a thick fog of exaggerations, both positive and negative.

Anyway, that's my opinion on the matter.
 
Mecha said:
These things have been around a long time. I destructively tested one of them about 7 years ago, including breaking it in half. I found it to have enormous grain, indicative of being way overheated in what I assume is an attempt to drive up the HRc numbers. The knife was not easy to break, it was surprisingly strong, and snapped viciously when it yielded. The edge itself was not tough and it was really easy to notch it deeply with a steel blade or otherwise damage it with impact. It didn't hold a fine edge very well despite obviously having been hardened, I suspect because of the poor grain structure and other bad things that happen when titanium alloys are overheated.

The super-secret custom-formulated titanium alloy thing is just pure nonsense. Back when I looked into these ti diving knives, I found that they're all made in China despite what a brand may claim, probably at the same plant, which is why all the various brand names of these ti diving knives look the same. You can get pallets of these things from Alibaba for like $30 a unit or less.

I've heard some people say their example works well, and I suspect they're not consistently heat-treated and some are better than others, also likely due to the irregularities in a lot of Chinese titanium alloys made from recycled ti. I know there's excellent ti alloy made there for other purposes than just basic consumer products, such as the defense and aerospace industries. Making the good stuff is expensive. Making a good blade out of it is difficult and easy to screw up.

As a diving knife, for prying, poking, and chipping at things on the sea floor, spearfishing, stabbing an attacking shark or maybe cutting a cord, it would be ok. Most non-knife people probably wouldn't even notice anything was off. Frankly, I'd rather just have a Magnacut knife or anti-shark sword for those tasks. But not a shiny one because then I'd get bit by a barracuda. XD

I don't like these knives simply because they generate a lot of additional BS concerning titanium, which constantly surrounds the metal like a thick fog of exaggerations, both positive and negative.

Anyway, that's my opinion on the matter.
Click to expand...

One other thing to add, about titanium alloys in general: If a set of test samples of an alloy are heat treated in the exact same way, the hardness numbers can easily vary as much as 4 points up or down from the average, a huge spread. Note the Ocean Master knife in the OP says 60-65. It may very well test within that span.

In the world of titanium metallurgy, the Rockwell Hardness test is not considered useful for determining or predicting mechanical characteristics. It's basically not used. This further complicates making blades from it, since some reasonable level of raw hardness is important for blades, but in my own work the heat treatment is focused on a fine-grained, tough result that doesn't yield, even on a thin edge. Edge not yielding = the target gets cut.

Back when I had a functioning hardness tester and was testing constantly, I found a study in which test tabs were heat treated with a computer-controlled system. The HRc spread on those was wider than my results doing it by eye. Titanium alloys are strange and react to anything that's happening to them, so watching carefully when processing each individual blade gives me the best results.

On top of that, you'll find a huge, huge difference in quality between various iterations of the same alloy.
 
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DocJD said:
But that's part of the romance and mystery = exotic allure ! :):cool:
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Bwahaha! In the end all I can do is keep it real for my own work. There's no stopping the ti hype train, or the ti denigration machine.
 
Mecha said:
These things have been around a long time. I destructively tested one of them about 7 years ago, including breaking it in half. I found it to have enormous grain, indicative of being way overheated in what I assume is an attempt to drive up the HRc numbers. The knife was not easy to break, it was surprisingly strong, and snapped viciously when it yielded. The edge itself was not tough and it was really easy to notch it deeply with a steel blade or otherwise damage it with impact. It didn't hold a fine edge very well despite obviously having been hardened, I suspect because of the poor grain structure and other bad things that happen when titanium alloys are overheated.

The super-secret custom-formulated titanium alloy thing is just pure nonsense. Back when I looked into these ti diving knives, I found that they're all made in China despite what a brand may claim, probably at the same plant, which is why all the various brand names of these ti diving knives look the same. You can get pallets of these things from Alibaba for like $30 a unit or less.

I've heard some people say their example works well, and I suspect they're not consistently heat-treated and some are better than others, also likely due to the irregularities in a lot of Chinese titanium alloys made from recycled ti. I know there's excellent ti alloy made there for other purposes than just basic consumer products, such as the defense and aerospace industries. Making the good stuff is expensive. Making a good blade out of it is difficult and easy to screw up.

As a diving knife, for prying, poking, and chipping at things on the sea floor, spearfishing, stabbing an attacking shark or maybe cutting a cord, it would be ok. Most non-knife people probably wouldn't even notice anything was off. Frankly, I'd rather just have a Magnacut knife or anti-shark sword for those tasks. But not a shiny one because then I'd get bit by a barracuda. XD

I don't like these knives simply because they generate a lot of additional BS concerning titanium, which constantly surrounds the metal like a thick fog of exaggerations, both positive and negative.

Anyway, that's my opinion on the matter.
Click to expand...

so then this titanium dive knife probably isn't being used by the US Army then........what a let down........
 
tokerblue said:
Get a Spyderco Salt. Or a Magnacut knife. Possibly a Magnacut Salt in the near future?
Click to expand...
Magnacut makes me drool. I've watched videos from people have trouble sharpening with anything but diamonds.

I get a beautiful edge on ceramic that will cut for miles.
 
I have just hardened Ti grade 5 to 60HRC. Grinding tomorrow to be sure it's not just the surface hardness. Making a dagger.
 
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