Any Metallurgists on here?

[vincereynard]

I am investigating having a one off tool made and I've been given quotes using normal HR steel and stainless. The tool will be 6mm thick and will only be hand used. Is there much difference in strength and elasticity between normal steel and stainless?

Stainless 304 is quoted at 4 times the price of stainless 316. As far as I know the 316 only has a small addition of molybdenum for added resistance against salt, (used in marine environment).
Is there much difference in their relative strength?

Should either be suitable for a hand tool?

[rgh0]

304 should be cheaper than 316 not more expensive. Both have similar mechanical properties. They both come is high, normal and low carbon versions depending on use ( low carbon for cryogenic use, and high carbon for high temperature use). Depends what sort of tool as to whether you want 304, 316 or a HR ( Hot rolled steel) or something else.


cheers
Rohan

[el-saturn]

.....................could we see a sketch. maybe the cheapest "chicken-wire" will do, strengthwise/loadwise. if thats enough, then machining it would be the next criteria AND the above will also be cheapest! sandy (PS i did NOT study metallurgy: but my training also included most machinable/casted etc.. MATERIALS)

[vincereynard]

.....................could we see a sketch. maybe the cheapest "chicken-wire" will do, strengthwise/loadwise. if thats enough, then machining it would be the next criteria AND the above will also be cheapest! sandy (PS i did NOT study metallurgy: but my training also included most machinable/casted etc.. MATERIALS)

It's a simple slip spanner. Laser cut, so no machining needed.

[Chancer]

Youngs modulus of elasticity.

304 & 316 Stainless both +/- 200 Gpascals

Plain carbon steel +/- 200 Gpascals also

Not sure what you mean by normal HR steel.

Dependant on the use the tool will get you may want to use high carbon steel heat treated after cutting.

[el-saturn]

..is that the actual tool? if so, get 'em to make one for you: by the looks of it, chicken-wire will do and is our cheapest. it's called st37 (37kg/mm2 tensile) sandy

[jk952]

If no specific need for stainless, a cold rolled steel better looking than HR but depends on thickness for ready availability (CR rolled thinner than HR typically). Sounds like strength isn't a real issue. If having a local tool shop do the laser cutting why not, with cash in hand, ask what he has on his shelf, scrap, or leftover bin...
You can google various types of steel for tensile strength etc. Some tool steels are for cutting applications so hard but brittle, others are for forming so toughness becomes the priority over strength. There is also pre-hard tool steels so strong without the need for heat treatment. All too much for a hand operated device I suspect, unless your planning on wacking it with a BFH.

[jk952]

I found this chart of mostly North American ASTM and SAE spec.'s of main chemistry, yield, tensile and elongation. You could look up stainless and compare. This is a photo, hopefully legible, not sure where the electronic version is if I even still have. Ksi is thousand pounds per sq.in. in case not familiar with the somewhat old school term.

Jack

[nomad]

Cold roll and case harden the jaws. Blacksmith stuff and cheap!

Kurt.