[cob]

hello everyone,
I am trying to make some tooling and seeing if some one can help me to choose the best kind of steel .
I would like it to be very strong, I am also thinking of heat treating to make it hard, that way it will last a long time, this will be use for punch and dies.
so far these are some steel types that I can think of (1018,1144,4140,and A36 ) if any one has a better idea I would greatly appreciated .

Thank you

[mactec54]

hello everyone,
I am trying to make some tooling and seeing if some one can help me to choose the best kind of steel .
I would like it to be very strong, I am also thinking of heat treating to make it hard, that way it will last a long time, this will be use for punch and dies.
so far these are some steel types that I can think of (1018,1144,4140,and A36 ) if any one has a better idea I would greatly appreciated .

Thank you

Would depend on what you want to use the punches for and what size, 4140 is the only one in your list that you can heat treat, the others can be case hardened but this as I said would depend on what you want to punch through the 1018 and the A36 is mild steel, this is not normally used for punch and dies

[machinehop5]

...quick answer is Tool Steel type
https://en.wikipedia.org/wiki/Tool_steel

[Jim Dawson]

A2 would be my first choice for punches and dies. Depending on the shape, you might be better to buy ready made punches & dies from Dayton Progress. https://www.daytonlamina.com/punch-die They'll make any shape you want for reasonable prices and a very quick turnaround time. I have buying from them for at least 40 years. Then all you need to do is make the punch & die holders, normally made from 4140 or 4150.

[cob]

thank you for the replies,
can 4140 also be case harden?
also do you guys have a good source where to buy some 3.5 O.D by 1.0 thick round blanks ?
thank you

[machinehop5]

thank you for the replies,
can 4140 also be case harden?
also do you guys have a good source where to buy some 3.5 O.D by 1.0 thick round blanks ?
thank you

...the information highway your welcome.
where abouts you at in usa?

DJ

[cob]

San Jose , California

[Jim Dawson]

Yes, 4140 can be case hardened.

Maybe try Metal Werx

or https://www.mcmaster.com/steel

or https://www.onlinemetals.com/

[vw_chuck]

If you are making a punch and die you most definitely need tool steel. Case hardened steel will fail miserably. The soft steel under the case will move and the case will crack in dramatic fashion.

[arolite]

A2 gets the nod for tools and dies every time. Heat treating : A2 is an air hardening steel. there are schedules online for proper heat and hold times depending on size of material.
case depth should be around .050-.060 at about R62 to a core tough of about R 58 . These numbers will vary when punching tougher materials such as stainless for example. Getting
a thick enough case helps with regrinds. Hunt down a heat treat company and ask if they have a vacuum furnace with inert gas and give them your specs and go from there.

Hope this helps

Arolite.

[peteeng]

Hi Cob - If your punch is 3.5" diameter you are going to require a big press. What thickness material are you punching? Peter

[Goemon]

Does anyone know how hardening steel would effect it's strength?

I thought that hardening steel made it brittle which was why they used differential tempering on swords.

Obviously cutting tools need hardening to retain a sharp edge longer. Do people harden dies too?

[peteeng]

Hi Goemon - With steel hardness and strength are proportional. So the harder it is the stronger it is. This also means the stronger it gets the more brittle it gets. So for every application there is a compromise to be had. To harden steel its heated to a high temperature then quenched. But this makes a glass like brittle material. Tempering is a process of softening the steel to the required strength and toughness. Some steels can be age hardened like aluminium this is a different process (maraging steels). The application may require part strength so the entire part is through hardened. The part like a cutting edge or linear rail may only need surface strength so carburising can be done to the surface only, which is cheaper then deep hardening. Dies that get thumped need strength so they are hardened to stop them breaking and improve their fatigue life. If its a cutting die then it can be case hardened vs deep hardening. Swords need to be hard on the outside so they can be sharpened to cut flesh. But they also need to be flexible to some degree to be able to bend without breaking so the centre is left softer to allow some flex. Each application has its own requirements. Temper, hardness, fatigue, flex, machinability, forgeability etc. Peter

https://www.associatedsteel.com/tech...version-chart/

https://en.wikipedia.org/wiki/Maraging_steel

https://www.nhtc.ie/hardening-of-tool-steels

image is a 4140 axle for a very large truck. I designed the axle. I'm not sure if this is after hardening or tempering but by the colour I'd say its the tempering temp. Hardening is 850C plus which is yellow. Tempering is 600-700C which is orange...

[joeavaerage]

Hi,
my go to steel for anything that requires strength and toughness is 4340, its a close cousin to 4140.
4340 and 4140 are chrome-molybdenum steels and don't just case harden but through harden. A heat and quench cycle will result in
hardening depths in excess of two inches. Its great stuff.

Both materials are commonly supplied as 'hardened and tempered', around900MPa-1000MPa. At that temper you can still machine it,
its about 32Rockwell C, so you have to be pretty committed to machining it but is possible. The good thing about hardened and tempered 4340 is that its
really tough, it makes great axles, shafts etc where there is significant impact.

I've only ever used hardened and tempered 4340, but if you harden it but omit the tempering you'll end up with about 1600MPa and about 50 Rockwell C,
so beyond my machining capability except for grinding. You can also carburize and even nitride 4340, and I imagine if you want genuinely hard edges on your die then you'll
need to do just that. Our local heat-treatment plant does this, but I understand both nitriding and carburizing require long cycle times and can be expensive.

Craig