Material Alternatives for hardened AISI 1045 1

[calvindral]

I have a highly visual part that requires a good aesthetic along with good strength and formability. It is currently made with a hardened 1045 steel .25" thick and about 2 inches wide. The issue we are having with the 1045 is that the breakout on the visual surfaces is very unsightly and looks like there is a scale buildup on the part.

Any suggestions for an alternative material. We are looking for something that would have similar deflection and fracture characteristics under load.

 

[Carburize]

What exactly do you mean by "the breakout on the visual surfaces" ?

 

[calvindral]

The edges of the stamped part are sheared and there is a shear zone and a breakout zone. The area where the material stops shearing (which in this material is a very small section, the shearing only occurs in about the 1st .030 - .050") leaves a very nasty uneven material condition. This is our show surface and is unacceptable. We have asked the supplier to look into a secondary operation to clean up that surface condition, but this adds cost (which we all know is not a good thing).

 

[NickE]

Fine Blanking? Otherwise you will have to use a secondary process to remove blanking burr and the break region.

(for your application if you need the strenght of hardened 1045 there really is no other material in your price range that will give you what you want.)

 

[swall]

Does the condition occur on every batch of stampings, or does it come and go?

 

[redpicker]

Is the material hardened before or after stamping?

What hardness is it?

If it is hardened after stamping, you might explore different annealing treatments prior to stamping to reduce the effect.

If it is hardened before stamping, you might want to explore changing the hardness requirement.

Also, depending on hardness level, you might also explore cold-rolled strip at an equivalent hardness which might have better shearing characteristics.

Finally, if the hardening is for wear resistance, maybe CR strip with a nitriding treatment (or other surface treatment) to improve wear resistance.

 

[jbel]

Is your question 'How do I make this thing look pretty for free or almost free?'

The nature of the stamping process will cause this 'breakout' to show along the entire shear profile. As suggested above, the use of a fine blanking process could alleviate the problem but there is a higher inherent cost involved in the process.

Also, a secondary operation is viable as well but you will incur additional expenses for that option too.

Redpicker's suggestions may well help but they will not eliminate the condition, only decrease the 'breakout' cross-section.

As you have said:

This is our show surface and is unacceptable.

If that is the case then you will have to incur costs in order to make it asthetically pleasing.

You may be able to add an additional station to the die that essentially coins the show surface. The coining process would displace material along the profile and give it a much more even appearance. Talk to you Toolroom Foreman or Die Designer and ask if your die can be adapted to include this step.

One more thing, you also ask for:

an alternative material... something that would have similar deflection and fracture characteristics under load.

Anything with similar fracture characteristics will display a similar appearance along the length of the cut. Unfortunately, you will most likely experience a condition similar to what you have now.