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It has come to my attention recently that gas turbine engines put a lot of stress on their blades. I hear that these blades are pretty tough and that they use a special process to make them. Has anybody ever worked with that steel before? Is it suitable for making knives or razors? Also, is there a good source for free time temp transformation tables? AKA isothermic tables?
yes a friend of mine has a hunting knife made out of this steel it will get sharp but not that sharp , i dont think that it would be a good razor , not for shure though try it on one and see how it comes out.
Where did he get it from? An airplane junk yard?
I am not sure but I thought that turbine blades were made out of an Aluminum Alloy. If this is the case I don't think they would make good razors.
bj
Some of them might be made out of aluminum, but it would make more sense to make them out of steel. But I'm not sure the process they use to 'grow' the blades would lend itself to working it into a different shape. I am also not sure that the mix used to make the steel would make for a good edge.
The original influence on the use of ATS-34 and 154CM were as steels that would handle the higher temperatures needed in aircraft turbine engines. They make fine blades.
Terry Knipshield has been working up some razors of CPM154 that are very nice. If the turbine blades are steel, they are likely something very similar. But, without engineering specs or some analysis of the material, you can't be sure.
I'll chime in here as I work for Pratt & Whitney as an inspector. I believe that these would not make good razors. In understanding the different sections of the engine: 1) anything from the hot section of the engine, the high and low turbine sections have cast blades with extreme curves and are usually hollow on the inside and woul break quite easily when you try to work them. 2) The foward section of the engine which is the cold section only has a couple of stages that might be used. Anything from the high compressor is too small to use for a blade as these airfoils range from a couple of inches in length to under an inch. The low compressor has a couple of stages of blades that might be used as they are bigger and longer but they still have quite a curve to them. most of these blades are stamped and then have some machine work done to them. If you could find a fan blade that might also be used as they are quite large but once again sometimes these blades are hollow to. The metal on these blades is quite hard, I'm not an engineer so I do'nt know the exact combo of metals they use. No they don't use aluminum for these blades. I have to blend and polish blades at times to remove minor damage (nicks and scratches) and this is no easy task as to the hardness of them. If you were to find one suitable enough to make into a razor I think that you will find that getting it thin enough and not having it break due to brittleness might be a problem.
If you do try this good luck to you. I would like to be proven wrong as I might have a good source for some scrap blades. Let us know how you make out.
Dan
Hollow huh? I wonder how thick the actual metal is then. I wonder if they use the curves in the metal to compensate for the difference in speed from the base to the tip or if there is a different content in the metal.
http://tbn2.google.com/images?q=tbn:...s/image020.jpghttp://tbn1.google.com/images?q=tbn:...79-0-large.jpg
These are a couple of cross sections of the hot section blades. The top photo is a really early design.
http://www.freepatentsonline.com/6544002-0-display.jpg
This is a inlet fan blade, what you see from the front.
http://www.solarnavigator.net/aviati...age_GE_J79.jpg
Longer blades are actually curved in two directions of the space to counter this and other problems.Quote:
Originally Posted by crazycliff200843
Then I think only older turbines actually had blades made of steel. Nowadays turbine blades are made from "superalloys" with very low iron content, like Nymonic (based on Nickel) or Vitallium (based on Cobalt), while research is pointing towards sinterized ceramics.
Hope this helps
SWEET!
Make a hollow razor! Big chopper of a razor, but still light and nimble.....
I dare ya!Quote:
Originally Posted by Seraphim
Don't forget titanium.
I'm sure that several generations of metals have occurred in the research of turbine blades since twenty years ago. Steels, by default, are much to heavy and low tech for good engines any more.
I read into the superalloys used a little bit last night and found that the newer stuff is indeed more nickle based than steel based. Some of it also has a lot of cobalt in it. And there seems to be a trend toward ceramics, but they are really expensive. Looks like ge and rolls royce are working on some kind of electric engines now. Whatever I eventually get my hands on, it should be somewhat corrosion resistant if it is the newer stuff, or mostly steel if it is rather old (at least 20-30 years?). I think I found some inlet blades on ebay. Some from God only knows what kind of engine, and some british military engines. There seems to be a pretty wide variety. They have some of the hollow collector blades on there as well. I just searched jet engine blade and jet turbine blade and got quite a few hits. Some of those blades were awfully small. They had some larger ones, though. All of them had some kind of curves. I think the metal would still be usable as long as there aren't any stress fractures. Or they could all be junk that has been through hell and back. Here's a link I found that has some info on the content of the alloys over the years, up to the mid 90s, I think. Rhenium seems to be well liked as well. A lot of the blades look like they have some kind of tracking info on them, so it might be easy to date it to a specific decade and then get a ballpark idea of what's in it.
Jet Engine: Turbine Blades and Temperature Text - Physics Forums Library
Enough of the swear words "GE and Rolls Royce" Thems fightin words:cen Oh just kiddin, I told you who I work for. Maybe not much longer, I don't know if you all have read the news but they (our socialist govt) are going to cancel the F22 Raptor program. That just might leave me with the other six milloin unemployed. I guess I better get back to restoring razors.
Well, I hope they don't make too many cuts where you work. But, if they do, 5 minutes in the supply room might actually be worth your while... Maybe oil prices will stay low and keep the russians poor enough to keep them from building too many planes that could even think about taking on a raptor if the program is getting scrapped.
Would that hurt P&W that bad? Obviously it's not preferable, but I thought they were in a fairly good position. At least you've got the F35 coming, as well as the A380 engines.Quote:
Originally Posted by tazz
I wouldn't think that using turbine blades would lend itself well to knives or razors. That being said, it would be pretty cool to be proven wrong.
Well with the way the economy is these days we aren't getting as many new orders for engines. The GP7000 (A380 engine) is still a limited production as there is only a few customers for them. The F35 is not slated to go into full production till 2011. Another big contract for us is the tanker contract that is still in limbo. Right now we are going through manditory one week furloughs, they are making us take them one day at a time so we can't collect. I figure if they cancel the F22 now I'll have about a one year vacation from there. The Airforce actually wants another 65 or so F22's wich relates to another 130 engines plus spares but they may not get them. That would most likley cancel that year long vacation.
I got one of the sets of blades in the mail a couple of days ago. They are awfully light for their size, which makes me wonder how much steel is in them. They are long enough to use as a razor, probably somewhere around 5 inches or so. They have quite a curve built into them, though, and are wider at the bottom than they are at the tip. To try and put an edge on one of them as is is going to be difficult. I could probably get a nice bevel started on the side that curves back onto itself, using one side of the blade as a guide for the other, but the other side poses the question of how to maintain a consistent angle as the blade curves away from it. I figure that one bevel will be much wider than the other, too, in order to get the desired angle. I will try and post some pictures of it after the weekend and maybe I will come up with an idea of how to put an edge on it. I might have to trim it down to a more manageable shape.
I also used to work for P&W, it was a good place to work!
If I were to use any kind of blades from the engine, I would go with Low Pressure Turbine blades, they are not hollow and in the slightly older engines they are a lot straighter.
But I have a suspicion that there are cheaper and easier ways to make hood razors.
It might prove easier and faster to try an old leaf spring or something, but I wanted to see if the metal of the turbine blades was any good.
Now a leaf spring is a good idea, you could make a meat chopper out of one of those. You would have to anneal it though just like you would if you were using a file. Then you would have to heat treat after you are done.
That's one of the reasons I was asking about the temp tables.
This is some tough stuff. I went through two cutoff wheels to cut through about an inch of material. I've cut the end off of a razor before and it barely made a dent in a cutoff wheel. There was quite a bit of twist but I think I found a straight enough piece in the blade that I could use. It will be warped and fairly thick, but I might be able to get an edge on it. I also have to figure out how to attach a handle to the base as well.
http://straightrazorpalace.com/membe...urbine-cut.jpg
http://straightrazorpalace.com/membe...urbine-top.jpg
Any luck yet? I bet you are having a heck of a time trying to drill a hole in that? Keep us informed.
Dan
I cut on it some more a couple of days ago. I'm almost done cutting it lengthwise and have gone through almost a dozen cut off disks. I might finish the cut next week and then try to shape it into something usable. I will say that even after the cuts I have made, there is no sign of oxidation. I've gotten my hands on a lot of different blades that have a handle on them already, but need a lot of the same work done on them, too. One of these days I will get my hands on a bench grinder or a belt sander and it will go a lot quicker. I'm taking some vacation pretty soon and should be able to make some decent headway on it.
I wouldn't want to put any metal that's come from an aircraft on my face.....YOU DON'T KNOW WHERE IT'S BEEN! :rofl2:
Might have better luck with silicon carbide bits that run 9-9.5 on the mohs hardness scale working with stuff that is that hard.
Widget supply (www.widgetsupply.com) has a bunch, are you using a dremel to do everything?
They also have diamond cut off wheels and drill bits as well as tungsten carbide bits. The diamond cut off wheels will probably lose their diamond bits on the edge pretty quick though.
It's been a while since I have posted, and I haven't made much headway with any turbine blades. The ones I found will take a bevel but I am having problems getting them sharp. For all the trouble it takes to get them into a useable shape and to put an edge on one, it is probably a better idea to just buy a nice piece of steel and work with that instead.
I remember talking to an RAF engineer years back about this up at RAF Leuchars. He told me the blades are made out single crystal titanium.
They're made out of titanium for the weight and the heat resistance (they cool down fast), and they become single crystal by a succession of heating and slow cooling to remove the microscopic fault lines in the metal.
Jet engines rotate at up to 100,000rpm, so the centrifugal force on even the small blades can be up to 40 tonnes. If they werent single crystal they would fly apart under the pressure.
The compressor blades are also hollow and have small needle sized holes on the leading and trailing edge and air is pumped through the blades to keep them cool.
The large front fan on turbofan engines doesnt have hollow blades, but they take a stupid amount of force when the engine is running at take off speeds. I cant remeber what it was exactly, but it was over 100 tonnes of centrifugal force IIRC.
The blades in these engines get replaced pretty often as you can imagine!
EDIT: Just seen Tazz's post with the pictures of the blades. You can see the holes clearly in those pics!
Interesting thread, made me think about a steam turbine I saw at a natural gas power plant in the laydown yard. From what I remember though, i believe it was some sort of alloy as well. Maker was GE though. One of the turbines was damaged in shipping and GE brought some Korean (where it was made/put together) engineer to look it over. The ended up installing it and it didn't even make it thru start-up trials. Something about balance issues. That thing had some huge blades though,,,