Need Tougher Carbide Insert
Need Tougher Carbide Insert
(OP)
We have a cut-off tool on a spring coiler using a Kennametal grade KC 850 square insert to make the cut. It is basically a shearing operation on spring temper 1095 strip approx 1/4" wide and .060" thick. Strip is coiled into a ring, then cut off. Although this is obviously a misapplication of a milling insert, I would like to know what grade of insert I could use that would be tougher and give longer life.





RE: Need Tougher Carbide Insert
Maui
RE: Need Tougher Carbide Insert
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Kennametal does supply cemented carbide grades that would be more specifically suited for this application. K3520 would be one example:
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RE: Need Tougher Carbide Insert
Maui--I was thinking along the same lines, perhaps M2. Not sure at this point how much leeway the shop has to reconfigure the cutter.
RE: Need Tougher Carbide Insert
RE: Need Tougher Carbide Insert
RE: Need Tougher Carbide Insert
Maui
RE: Need Tougher Carbide Insert
RE: Need Tougher Carbide Insert
RE: Need Tougher Carbide Insert
"Dunking" is not a valid cryo process because of the extreme temperature gradients it creates. A slow cool down to cryogenic temperatures is required, then the part needs to be held there for a period of time.
By the way, cryo treatment of the above mentioned HSS inserts would be very advantageous also.
Why is cryo not used more? It is not unusual for companies that make products that are benefited by cryo to tell us they do not want to sell fewer products. They end up selling a lot fewer when their competition starts using it. Others give the excuse that they have to understand why it works even after they see it work. I would have loved to see that in the early process of heat treating metal. Imagine the knight Sir Dumbalot claiming he would not use a harder and stronger sword blade because he didn't understand why heat treating made it harder and stronger. He would have been a candidate for a posthumous Darwin award. We get a lot of silly excuses, so many that we started a list of them on our web site.
RE: Need Tougher Carbide Insert
RE: Need Tougher Carbide Insert
When I do carbide failure analysis I generally look at the part 17 different ways. See the information in the following link to see the different considerations.
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2. The KC 850 is an old grade and there've been tremendous advances in carbide since Kennametal introduced it. However, since Kennametal never identified the underlying grade, it could be anything. Kennametal has a history of changing the compositions of their grades while still using the same identifiers.
3. There are some extremely tough new grades. Some of the old grades been greatly enhanced with modern technology. An example would be a 20% cobalt with some micron or nano grain technology. This ends up producing an extremely tough and extremely long wearing carbide part.
4. I have been following cryo technology for decades and would love to use it but so far it is neither predictable nor reliable. Anecdotal evidence indicates that when it works it can work extremely well however it may or may not work and there doesn't seem to be any way to predict that without actually using it.
If you like the idea of Cryo, then go ahead and try it. It doesn't seem to make things any worse.
Conclusion: We have quit using Kennametal for two reasons. 1. Their tech support is horrible. It is extremely difficult finding anyone who really knows anything. As mentioned above we have had projects going along swimmingly and then Kennametal change the composition of the grade without telling us causing the project to fail disastrously.
I would not place a lot of faith in cryogenics unless they could predict performance and guarantee consistent improvement. Every time we've asked about the reliability of the process, we have been told that they won't charge us if it doesn't work.
Thomas J. Walz
Carbide Processors, Inc.
www.carbideprocessors.com
Good engineering starts with a Grainger Catalog.
RE: Need Tougher Carbide Insert
RE: Need Tougher Carbide Insert
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RE: Need Tougher Carbide Insert
Thomas J. Walz
Carbide Processors, Inc.
www.carbideprocessors.com
Good engineering starts with a Grainger Catalog.
RE: Need Tougher Carbide Insert
Thomas J. Walz
Carbide Processors, Inc.
www.carbideprocessors.com
Good engineering starts with a Grainger Catalog.
RE: Need Tougher Carbide Insert