The hard coating on Ti alloys after heat treating in air is commonly called alpha case. The longer the heat treat, the deeper it goes. It is very hard and can skew your hardness results if not completely removed. It will break tooling during machining operations unless you can get under it and peel it off. Industry typically “pickles” the material in acid after heat treat to remove the alpha case or uses a vacuum furnace to prevent it from forming. Good channel. Good stuff. Keep it up. Cheers.
Tim: When doing hardness sampling, good practice in any averaging of values is to through out the lowest and the highest and average the remaining. I would try to do 7 or 8 samples, toss 2 and average 5 or 6.
Correct, that's the way I was taught. Throw out the highest and lowest. I wonder why he didn't cut something like a 6" piece and test along the side. The Rockwell hardness tester came with holders for round stock.
With small data sets with wide variance like this the most accurate results come from either using the mode (most common value) or median (center value when sorted low to high). Using the mode is preferred but can be misleading if only two values agree so the easy way is three or more agree use the mode. Else use the median. Still it’s a judgement call, when in doubt use Kent’s method.
You might consider getting the stainless steel foil knife makers use to seal out air/oxygen when heat treating. It should prevent the titanium from oxidizing and scaling
Not enough. It needs to be in an inert atmosphere, even nitrogen is reactive towards titanium at high temperature. So the entire heat treat forge would have to be purged with argon.
If you can find a heat treat oven that is sealed with a Gas inlet that would be ideal. So if you did a let a bit of argon flow during the HT you would get no scaling. And if you want to make a durable gold colored coating heat to 700-1100C and add nitrogen. It's almost a perfect gold color and super durable. I nitride a Ti spork about 6 years ago and it's still perfect.
Glad you’re back tim. Love the experiments. Eat some Timbits for us. When we flew back to Hong Kong from Texas we had to change our flights and we’re not able to go through Vancouver unfortunately. My wife missed her timbits
Hi Tim, Love what you do! Here's one for you with the hardness tester (sweeeet kit btw and shout out to the fine fellow who sent it your way to educate the masses!) - Stainless steel 304 plain AND work hardened. In fact, how much harder does work hardening effect everything - like those copper chisels they made the pyramids with. Haha.
Or how hard do you have to work the stainless to change the grain structure into hard-what is it called? Austentic? Yeah, covering terms like this if you're going to work garden stainless would be the easiest part, as well as clarifying the differences between tough, hard, and ductile etc instead of having a video where you just f around with some metal and boggle at the results. It's not 2008 TH-cam anymore. People use tripods and editing!
Thanks for the video Tim! When I saw the title, the first words out of my mouth were: “Why would it need to be hardened any more than it already is?” 😂
I just got started on this video and I have used a hardness tester quite a bit. As long as you keep it calibrated this is absolutely 100% no doubt about it a scientific experiment.. the only difference between you and anybody else is how accurately you can measure and you seem to have a very good piece of equipment so 🍻🍻🍻🍻🍻👍👍👍 that being said you should most definitely polish the surface you're testing on a whetstone not a hot grinder..
So happy to see a new video Timothy. Very nice video. Very well explained videos. Can't wait to see more videos soon. Keep up the great craftsmanship and hard work my friend timmothy. Forge on. Keep making. God bless.
You need to maintain an air free environment to anneal titanium without creating molecules of TiOx or TiN which have completely different physical properties. Ar is the easiest and most common gas to use. In semiconductors you would have a SiC (silicon carbide) container purged with argon for processing.
Yeah Also the flame is oxidizing if he changed the ratio of air and gas he could get it to a reducing flame or neutral, a reducing flame would eliminate 99.99% of oxidation and with certain metals with a high enough temperature it can even convert the oxidized metal back to the original metal, It can leach carbon into some metals tho if carbon is dissolvable in it if its a sooty and very fuel rich, It could be unwanted or sometimes good if you want the surface to be harder with extra carbon such as in iron
This is slightly interesting but all of this is already known and available information. Grade 4 is commercially pure Ti and can't be hardened. Grade 5 is Ti-6Al-4V, the most common alloy and can be hardened by heat treating, pickling and aging processes as you already know.
I think titanium being hard is a common misconception. Because it's hard on machining tools. It's very tough not hard, that's why it doest make good knife blades. Cool video though thanks for sharing 👍.
Love seeing more TH-camrs doing hardness test, I do my test with a UCI hardness tester, not to sure how it would do with titanium though, maybe i’ll do some test in the future too..
One thing to keep in mind for age hardening / ageing / precipitation hardening, be that 2000, 6000 or 7000 series aluminium, maraging steel (MAR250, MAR300, MAR350, etc.) or the PH steels (17-4 PH, 15-5 PH, PH 13-8 Mo, etc.) is that the hardening process is driven by _time at temperature_ to allow for precipitates to form. The temperature determines the solubility and mobility of the precipitation forming elements, so it's temperature that dictates the size and distribution of the precipitates that form, and the resulting mechanical properties. Quenching can be important after solution annealing, but by and large, quenching isn't required after ageing / precipitation hardening.
I work with titanium on a regular basis. It is very unforgiving! Deburring and finishing and polishing. Its a love hate thing!lol!! Love your content!!🤘
It's definitely worth looking at the Gough Custom channel on TH-cam. He's a small knife maker and is incredibly methodical, and has documented much of his process. Lovely chap too.
2:55 Titanium gains its strength when mixed e.g. with steel. Titanium also starts hardening around 200° C Idk at what temperature it anneals but looks like the cutting wheel hardened and anneal on some spots. I think The old Tony worked with it on a lathe and you need massive amounts of cooling and when drilling, keep a steady pace or it hardens and you need carbide to bite through. Annealing is done in several stages where you drop the temperature, keep it a specific amount of time, before lowering again to a certain level and keep and so on.
I work in an aerospace machine shop and we do a lot of Ti that has been sent out for harding. I don't know a lot about it but I do know the atmosphereric environment is very important. We weld it also and it has to be a zero oxygen environment .
Hey Tim you should go check out tyrell knifeworks here in TH-cam land. If I recall correctly he has the same hardness tester as the one you now have. If you have any questions he may be able to assist you in getting you up to speed and calibrated and all that good stuff. Plus I think you might also like his work. Anyways keep up the good work I always enjoy watching your work.
You should do a light reading about hardening titanium. And how the different grades/ alloys work. There s only a few that is recommended for hardening. First thing is to get an electric heattreating owen and use some nobelgas to keep it from oxidizing. Argon would do fine... But it´s alot harder to play with titanium and succeed than you might think. I read a little about it two years ago, but don´t remember it so good. I have Gr.1, Gr.2 and Gr.5 at home if I don´t remember wrong, and gave up my plans of hardening them with the equipment I curently have...
Took off the hard part Properly, need exact numbers of temps with all temp treatments, as well as timing and size of mat . I believe water is best but also needs temperature control. I have not been able to keep an edge compared to a good nife . Better then most but not my W2 Tool
When checking the hardness of a sample before or after quench hardening don’t use a grinder that causes it to hot that will ruin the sample causes soft or hard spot throughout the samples surface
Well you can take and look up the process of how they plate with Titanium. The spoons as an example have a coating that is very hard along with the plating done on titanium engine parts and the coating on that. Mostly cause Titanium itself without the coating would mess up and gaul against everything metal.
You can make the next witch king of angmar flail out of titanium, that way it won't be as heavy, maybe you can even use it yourself or get a strongman to use it.
Great vid man! Just curious if this was with Rockwell HRC? And I've been wondering about HT'ing ti for a while, so I really appreciate the video, but I'm also curious about softening ti. It feel like, it doesn't matter what you do to ti, it just makes it harder lol.
Would be interesting to see what happens in a reducing forge, (charcoal etc) to reduce oxidation, as noted in other comments re: vacuum furnaces used for commercial heat treatment. Non-ferrous heat treats and aging seem pretty weird when you're used to steel.
How would work hardening compare to a heat treat? Rifle barrel manufacturers sometimes take advantage of this by cold hammer forging their barrels. I'm curious as to whether or not this would apply to titanium. Given it's reactive nature, it may be a safer option.
I'm curious put a rod of steel and a rod of titanium and maybe some hardened steel under a cut off wheel with the same 5lbs of weight and time how long it takes to cut through.
Great vid, thanks, if you haven't turned Ti before?, carbide insert tooling works great, I pretty much always use grade 5 (6Al4V), it's a bitch to drill deep, but otherwise great fun to machine, grade 2 is vey much like aluminium to machine. It would be interesting to see after HT, if cryo has any effect???, I have a Paragon HT oven, but the thought of it running for 8 hours, doesn't fill me with happy thoughts;), Also, was the testing done with the point (Rc), or with the ball (Rb)?, the ball might be better??, Have a good one, Scott
Oh man, that's gonna be hard.. to do.. and oxygen ruins process if you can't heat it in inert place. And induction heat is friend. Plus different alloys of titanium are different headaches 😩 But try, try and test, you will gonna make it. Don't heat too long (because oxygen) Iam intrested alloy of ti,chrome and tungsten. And if it need some doups then it needs and those are allowed.
Wow, I've never seen Ti cut with an abrasive cut-off disk. Also I have never, seen Ti heated without protective tool wrap. Always square-off round bars in the lathe before testing hardness. l don't know what those numbers are because everyone is familiar with rockwell B, or rockwell C numbers. Why not test Ti gr 2 vs. gr 5? What is grade 4?
hey so i find this interesting but i have no idea what the numbers mean . I know the higher the number the harder it is but what it is compared to diamond some other material that we all know . would be a nice addition to your video for a noobie like me
Hardness measurements are a bit weird; what this tool is telling you is literally "how deep did this particular indenting tool go into the part", which is what the rockwell hardness scales all actually mean (for rockwell C it's literally 100 - (depth in mm * 500) for a 120 degree diamond cone with a 0.2mm spherical tip and 150kgf force). I'm not sure if there's any similar test that's well defined for diamond, as I expect diamond to break rather than plastically deform in this kind of test even if we had a good material to make a probe out of. On the other hand, while hardness is pretty difficult to map to bulk physical properties of the metal (the physics of the test aren't terribly simple), it's a really easy and quick test to do and it _does_ correlate well with the other physical properties for particular materials or repeated parts, so you use it as a sort of proxy for destructive tests and such. You just run the tests and measure both hardness and the property you want to be sure about and build up the mapping empirically. For some reference points for the Rockwell C scale: hard knife steels end up somewhere like 55-66, tool steels can go up to 70 but get brittle up there, and axes usually are more like 45-55 given the hard use and need not to chip.
I researched all sorts of metals via the Encyclopedia Brittanica for my Dungeons and Dragons character decades ago and learned the term "ductility" when the subject of titanium came about. The metal is famous for being "hard" and especially for being light, but the capacity for resisting whatevertheterm for long-term deformation in response to load is what I internalized by the gods-named-element. While only in this decade have I actually delved into welding and metallurgy in actuality, and learned sophisticated terms as martenistic, austinetic etc, my general understanding is that the metal is a lot more like silly putty than the average person presumes. So your original numbers in the teens are very unsurprising.
I've heard someone making titanium Thermite which burned as bright as magnesium and lit places miles away with the brightness akin to a lightning strike. Yeah, like aluminum, the stuff oxides pretty bad (well?) when hot and those 3 metals, aluminum, magnesium, and titanium were behind the necessity of developing Tungsten Inert Gas welding as the shielding gas enveloping the molten metal and protecting it from the atmospheric oxygen.
![ILLSLICK - WINTER IS COMING [Official Video]](http://i.ytimg.com/vi/dwTMeM1zIhQ/mqdefault.jpg)
The hard coating on Ti alloys after heat treating in air is commonly called alpha case. The longer the heat treat, the deeper it goes. It is very hard and can skew your hardness results if not completely removed. It will break tooling during machining operations unless you can get under it and peel it off. Industry typically “pickles” the material in acid after heat treat to remove the alpha case or uses a vacuum furnace to prevent it from forming. Good channel. Good stuff. Keep it up. Cheers.
Sounds like you've worked with the stuff, or do you just read a lot? Either way good info. Thanks
@@BCM1959 I’ve worked in manufacturing specialty Ti alloys for a while. Glad you found it interesting.
Are you able to say how many HRC alpha cases has?
@@jistyclovek4693 If I remember correctly, it can be about 65 HRC at the very surface. It easily scratches hardened tool steel.
I'm looking in to balisong trainer making. May I ask about Timascus? Is it harder to milling compare to TC4 (Gr5) Titanium?
Glad to see the tester made it to you and is getting used. I could not have done it justice
Thank you so much! I am loving this thing way more then I ever thought I would!
Thank you for helping make this channel even more interesting and fun to watch.
A big 👍 from me to you James.
Yep, an HT oven is called for, both for this experimental series and for your ax heads! Just ponied up the big bucks for one myself.
Tim: When doing hardness sampling, good practice in any averaging of values is to through out the lowest and the highest and average the remaining. I would try to do 7 or 8 samples, toss 2 and average 5 or 6.
Correct, that's the way I was taught. Throw out the highest and lowest.
I wonder why he didn't cut something like a 6" piece and test along the side. The Rockwell hardness tester came with holders for round stock.
With small data sets with wide variance like this the most accurate results come from either using the mode (most common value) or median (center value when sorted low to high). Using the mode is preferred but can be misleading if only two values agree so the easy way is three or more agree use the mode. Else use the median. Still it’s a judgement call, when in doubt use Kent’s method.
You might consider getting the stainless steel foil knife makers use to seal out air/oxygen when heat treating. It should prevent the titanium from oxidizing and scaling
Not enough. It needs to be in an inert atmosphere, even nitrogen is reactive towards titanium at high temperature. So the entire heat treat forge would have to be purged with argon.
@@taiwanluthiers I have a door that had argon in the window. It got out. It's pesky. Difficult to seal in.
If you can find a heat treat oven that is sealed with a Gas inlet that would be ideal. So if you did a let a bit of argon flow during the HT you would get no scaling. And if you want to make a durable gold colored coating heat to 700-1100C and add nitrogen. It's almost a perfect gold color and super durable. I nitride a Ti spork about 6 years ago and it's still perfect.
That creates ti-nitride TiN
Glad you’re back tim. Love the experiments. Eat some Timbits for us. When we flew back to Hong Kong from Texas we had to change our flights and we’re not able to go through Vancouver unfortunately. My wife missed her timbits
Need a heat treat oven and a big bottle of argon. Think it would be best to not let it get oxidized?
Good idea , purge it during the process!
Hi Tim, Love what you do! Here's one for you with the hardness tester (sweeeet kit btw and shout out to the fine fellow who sent it your way to educate the masses!) - Stainless steel 304 plain AND work hardened. In fact, how much harder does work hardening effect everything - like those copper chisels they made the pyramids with. Haha.
Or how hard do you have to work the stainless to change the grain structure into hard-what is it called?
Austentic? Yeah, covering terms like this if you're going to work garden stainless would be the easiest part, as well as clarifying the differences between tough, hard, and ductile etc instead of having a video where you just f around with some metal and boggle at the results. It's not 2008 TH-cam anymore. People use tripods and editing!
Thanks for the video Tim!
When I saw the title, the first words out of my mouth were: “Why would it need to be hardened any more than it already is?” 😂
I just got started on this video and I have used a hardness tester quite a bit. As long as you keep it calibrated this is absolutely 100% no doubt about it a scientific experiment.. the only difference between you and anybody else is how accurately you can measure and you seem to have a very good piece of equipment so 🍻🍻🍻🍻🍻👍👍👍 that being said you should most definitely polish the surface you're testing on a whetstone not a hot grinder..
So happy to see a new video Timothy. Very nice video. Very well explained videos. Can't wait to see more videos soon. Keep up the great craftsmanship and hard work my friend timmothy. Forge on. Keep making. God bless.
You need to maintain an air free environment to anneal titanium without creating molecules of TiOx or TiN which have completely different physical properties. Ar is the easiest and most common gas to use.
In semiconductors you would have a SiC (silicon carbide) container purged with argon for processing.
Yeah Also the flame is oxidizing if he changed the ratio of air and gas he could get it to a reducing flame or neutral, a reducing flame would eliminate 99.99% of oxidation and with certain metals with a high enough temperature it can even convert the oxidized metal back to the original metal, It can leach carbon into some metals tho if carbon is dissolvable in it if its a sooty and very fuel rich, It could be unwanted or sometimes good if you want the surface to be harder with extra carbon such as in iron
Glad to see you are back and playing in the shop.👍 Hope your holidays were good 😊
This is slightly interesting but all of this is already known and available information. Grade 4 is commercially pure Ti and can't be hardened. Grade 5 is Ti-6Al-4V, the most common alloy and can be hardened by heat treating, pickling and aging processes as you already know.
I think titanium being hard is a common misconception. Because it's hard on machining tools. It's very tough not hard, that's why it doest make good knife blades. Cool video though thanks for sharing 👍.
Very interesting, I always enjoy your videos but this one was extra interesting. Can't wait to see what you're going to make with that stuff.
Love seeing more TH-camrs doing hardness test, I do my test with a UCI hardness tester, not to sure how it would do with titanium though, maybe i’ll do some test in the future too..
One thing to keep in mind for age hardening / ageing / precipitation hardening, be that 2000, 6000 or 7000 series aluminium, maraging steel (MAR250, MAR300, MAR350, etc.) or the PH steels (17-4 PH, 15-5 PH, PH 13-8 Mo, etc.) is that the hardening process is driven by _time at temperature_ to allow for precipitates to form.
The temperature determines the solubility and mobility of the precipitation forming elements, so it's temperature that dictates the size and distribution of the precipitates that form, and the resulting mechanical properties. Quenching can be important after solution annealing, but by and large, quenching isn't required after ageing / precipitation hardening.
I work with titanium on a regular basis. It is very unforgiving!
Deburring and finishing and polishing. Its a love hate thing!lol!!
Love your content!!🤘
It's definitely worth looking at the Gough Custom channel on TH-cam. He's a small knife maker and is incredibly methodical, and has documented much of his process. Lovely chap too.
2:55 Titanium gains its strength when mixed e.g. with steel.
Titanium also starts hardening around 200° C
Idk at what temperature it anneals but looks like the cutting wheel hardened and anneal on some spots.
I think The old Tony worked with it on a lathe and you need massive amounts of cooling and when drilling, keep a steady pace or it hardens and you need carbide to bite through.
Annealing is done in several stages where you drop the temperature, keep it a specific amount of time, before lowering again to a certain level and keep and so on.
I work in an aerospace machine shop and we do a lot of Ti that has been sent out for harding. I don't know a lot about it but I do know the atmosphereric environment is very important. We weld it also and it has to be a zero oxygen environment .
Hey Tim you should go check out tyrell knifeworks here in TH-cam land. If I recall correctly he has the same hardness tester as the one you now have. If you have any questions he may be able to assist you in getting you up to speed and calibrated and all that good stuff. Plus I think you might also like his work. Anyways keep up the good work I always enjoy watching your work.
Thank you for holding up the titanium bandwagon!
Next time try a quench in ice cold ammonia
Nice video as always, so interesting! I love the thumbnail btw 😂😂😂
Cool video never thought about if you could harden titanium
Know I know thanks
Yo Tim! When you do averages of these kinds of things, throw the highest value and lowest value out before you calc the average…..
Love me some back woods hillbilly science. Keep it coming!
Later on “THIS OLE BLACKSMITH”…. Tim asks his wife … HEY HONEY, Do you still have that really old diamond ring you grandmother gave you???
Super interesting my guy! Keep it up!
Who was I just watching Tim the blacksmith or IRON STINE the Scientist ?. Keep up the good work mate .. :)
You should do a light reading about hardening titanium. And how the different grades/ alloys work.
There s only a few that is recommended for hardening.
First thing is to get an electric heattreating owen and use some nobelgas to keep it from oxidizing.
Argon would do fine...
But it´s alot harder to play with titanium and succeed than you might think.
I read a little about it two years ago, but don´t remember it so good.
I have Gr.1, Gr.2 and Gr.5 at home if I don´t remember wrong, and gave up my plans of hardening them with the equipment I curently have...
Dennis the menace has been at it with the Chiclets again...
Took off the hard part
Properly, need exact numbers of temps with all temp treatments, as well as timing and size of mat . I believe water is best but also needs temperature control. I have not been able to keep an edge compared to a good nife . Better then most but not my W2 Tool
When checking the hardness of a sample before or after quench hardening don’t use a grinder that causes it to hot that will ruin the sample causes soft or hard spot throughout the samples surface
hey tim. welcome back. missed ya
Very interesting video as usual. I believe to harden titanium without contamination it needs to be done in a vacuum heat treating oven.
That’s one nice and juicy thumbnail you made there :) 👍😁
Well you can take and look up the process of how they plate with Titanium. The spoons as an example have a coating that is very hard along with the plating done on titanium engine parts and the coating on that. Mostly cause Titanium itself without the coating would mess up and gaul against everything metal.
Gotta try that inconel.
"need a heat treat oven" next vid "I want to thank today's sponsored raid Shadow Legends" 🤣🤣🤣
I used to have to use a rockwell machine at work. You and damage the diamond and get bad readings. just fy!! thx for the great videos
I love this kind of stuff. I think the best way to out stuff is just do it
I'll continue watching anyway but I do appreciate science!
One word. Paragon. 👍
I heat treated my grade 5 with motor oil and it turned out great
I buy from those guys a bunch, I x-ray my purchases and it's legit, unlike other sellers.
I wonder what you could do with titanium carbide
I’ve seen good reviews for the HotShot heat treat ovens
You can make the next witch king of angmar flail out of titanium, that way it won't be as heavy, maybe you can even use it yourself or get a strongman to use it.
Thank you, add my knowledge about gr4 & gr5.. 🙏😀
It would be interesting to use something to help prevent oxidisation of the outer surface during HT
You didn't try hardening it from room temprature and "quenching" it in liquid nitrogen to see what that does . Titanium work hardens really well.
Hey try with different sheets having different grades and i appreciate your work
You need to look up the instructions for using a hardness tester. Always polish the surface. You could have just used the v block and tested the o. d.
try a small electric furnace/kiln and an argon atmosphere. that way no oxidation
Great thumbnail 👌
Edit: the video was good too
Great vid man! Just curious if this was with Rockwell HRC? And I've been wondering about HT'ing ti for a while, so I really appreciate the video, but I'm also curious about softening ti. It feel like, it doesn't matter what you do to ti, it just makes it harder lol.
Would be interesting to see what happens in a reducing forge, (charcoal etc) to reduce oxidation, as noted in other comments re: vacuum furnaces used for commercial heat treatment. Non-ferrous heat treats and aging seem pretty weird when you're used to steel.
Hell ya
Gg
this is Science jim
Bro,! You just justified a big purchase... lol but yeah, you need a HT oven.👍
Please do the 8 hours test!
You can also try work hardening it
Nice video
Super interesting. Would S/S foil wrap reduce oxide?
Off topic question - sorry. TIm, where can I get your amazing black jacket from??
How would work hardening compare to a heat treat?
Rifle barrel manufacturers sometimes take advantage of this by cold hammer forging their barrels. I'm curious as to whether or not this would apply to titanium. Given it's reactive nature, it may be a safer option.
Cool vid! 👍👍
Yoi are mad and I like it. I trying to learn something about titanium. By now, all I know is: I can deal with steel but not with titanium yet.
You should do a 16 hour heat treat…
"the only difference between screwing around and science is writing it down" -adam savage
With large variability in the data, it may be better to use the modal value instead of the mean
Haha I knew this was gonna turn into a new toy to play with! Love it, I’d do the same thing, I’d be testing every knife I own! 👍
I'm curious put a rod of steel and a rod of titanium and maybe some hardened steel under a cut off wheel with the same 5lbs of weight and time how long it takes to cut through.
Great vid, thanks, if you haven't turned Ti before?, carbide insert tooling works great, I pretty much always use grade 5 (6Al4V), it's a bitch to drill deep, but otherwise great fun to machine, grade 2 is vey much like aluminium to machine.
It would be interesting to see after HT, if cryo has any effect???, I have a Paragon HT oven, but the thought of it running for 8 hours, doesn't fill me with happy thoughts;), Also, was the testing done with the point (Rc), or with the ball (Rb)?, the ball might be better??,
Have a good one,
Scott
Can you make a video. How to us the instrument?
Oh man, that's gonna be hard.. to do.. and oxygen ruins process if you can't heat it in inert place. And induction heat is friend. Plus different alloys of titanium are different headaches 😩
But try, try and test, you will gonna make it. Don't heat too long (because oxygen)
Iam intrested alloy of ti,chrome and tungsten. And if it need some doups then it needs and those are allowed.
Tim you should forge them then air cool and check the hardness, I'm curious if the heat plus work will harden them
The experience I have had is grade 5 work hardens. Threading it is not easy either. Just my experience though.
Do nitrogen quench and explain hard scale
Wow, I've never seen Ti cut with an abrasive cut-off disk. Also I have never, seen Ti heated without protective tool wrap. Always square-off round bars in the lathe before testing hardness. l don't know what those numbers are because everyone is familiar with rockwell B, or rockwell C numbers. Why not test Ti gr 2 vs. gr 5? What is grade 4?
This ok but I'd like to see more knives and cool things
Incoming Paragon sponsorship
what it tempering temperture for grade 5, to be use in die casting...mould making
Nice interesting video! Hope you're feeling ok.
Could you test the hardness of red hot steel?
hey so i find this interesting but i have no idea what the numbers mean . I know the higher the number the harder it is but what it is compared to diamond some other material that we all know . would be a nice addition to your video for a noobie like me
Hardness measurements are a bit weird; what this tool is telling you is literally "how deep did this particular indenting tool go into the part", which is what the rockwell hardness scales all actually mean (for rockwell C it's literally 100 - (depth in mm * 500) for a 120 degree diamond cone with a 0.2mm spherical tip and 150kgf force). I'm not sure if there's any similar test that's well defined for diamond, as I expect diamond to break rather than plastically deform in this kind of test even if we had a good material to make a probe out of.
On the other hand, while hardness is pretty difficult to map to bulk physical properties of the metal (the physics of the test aren't terribly simple), it's a really easy and quick test to do and it _does_ correlate well with the other physical properties for particular materials or repeated parts, so you use it as a sort of proxy for destructive tests and such. You just run the tests and measure both hardness and the property you want to be sure about and build up the mapping empirically.
For some reference points for the Rockwell C scale: hard knife steels end up somewhere like 55-66, tool steels can go up to 70 but get brittle up there, and axes usually are more like 45-55 given the hard use and need not to chip.
i like that black coat, can you tell me the brand name please?
try a high heat then liquid nitrogen
More titanium testing and test can you made something from it.
would a HT oven company give you one as a sponsership thingy???
Wonder if purging with argon in my ht oven would keep from scaling?? 🤔
I researched all sorts of metals via the Encyclopedia Brittanica for my Dungeons and Dragons character decades ago and learned the term "ductility" when the subject of titanium came about. The metal is famous for being "hard" and especially for being light, but the capacity for resisting whatevertheterm for long-term deformation in response to load is what I internalized by the gods-named-element.
While only in this decade have I actually delved into welding and metallurgy in actuality, and learned sophisticated terms as martenistic, austinetic etc, my general understanding is that the metal is a
lot more like silly putty than the average person presumes.
So your original numbers in the teens are very unsurprising.
I've heard someone making titanium Thermite which burned as bright as magnesium and lit places miles away with the brightness akin to a lightning strike. Yeah, like aluminum, the stuff oxides pretty bad (well?) when hot and those 3 metals, aluminum, magnesium, and titanium were behind the necessity of developing Tungsten Inert Gas welding as the shielding gas enveloping the molten metal and protecting it from the atmospheric oxygen.
8 hour test for tour next video?
Please put the safety guard back on your grinder
Dip them in liquid nitrogen and see if further hardens them
the difference of science and messing around in the backyard is whether or not you write it down
Well if nothing else Ti makes some sparks.
when you heat it for 3 hours was it any reductive atmosphere