Ion Nitriding application 1

[mewhg]

We are having a problem with wear on a 1/8' thk 4130 sheet metal lever. Currently the lever is Q&T to 50 HRC.

We are thinking about taking the existing levers and having them Ion Nitrided about 0.010" deep and then possibly PVD coating.

I am aware that the 50 HRC lever would decrease in hardness to about 35 HRC but this would be acceptable as long as the nitrided case was in the 55 HRC or greater range.

Am I going in the right direction here? Could someone recommend a PVD coating that could be applied over the nitriding?

 

[TVP]

Bill,

I think your proposal is good. Obviously the whole part does need to be 50 HRC if surface wear is the concern. Nitriding and then PVD coating is becoming popular for highly stressed tool components such as punches & dies for cold forming/forging. I would talk to Oerlikon Balzers, Sulzer Metco or similar about a "duplex" treatment, which is the designation used for PVD over nitrided steel. The exact PVD layer will depend on the mating components, temperature, etc. Here is a brief description from Sulzer:

http://www.sulzermetco.com/en/desktopdefault.aspx/tabid-100/2963_read-8145/

 

[mewhg]

Thanks TVP,

I getting some samples that are Ion Nitrided .010" thk with an Aluminum Chromium Nitride coating. I will report back with how it goes.

 

[tripleZ]

We had a rep in here from Philos Technologies the other day selling a process that is more of a titanium nitride infusion...not really a CVD coating, but it has a depth similar to case hardening (somewhere around 0.005" I think). It will lower the base hardness of your material, but gives the outer layer a hardness of somewhere around 70 HRC.

If the PVD coating doesn't work as planned, that may give you a potential option.

 

[mewhg]

I had a go at this last week. Ionic Technologies in SC did the nitriding and PVD coating. A very professional outfit.

In testing the PVD/nitriding wore thru at one critical location after 20,000 cycles of the part. I think it was due to the lower hardness of the core 4130 not being able to support the load. At another location of the part where there is quite a bit of sliding wear but the load is not so great the component had absolutely no wear at all.

Now the challenge is to find a hot work steel such as H13 in 1/8" thickness and try this again with a higher core hardness.

Thanks all for the replies.