4150 "toughness"
4150 "toughness"
(OP)
i have some 4150 and i need to heat treat them for maximum toughness. What Rc value is this at? I assumed 50, but i recieved the parts back at 60+. Is it possible to anneal them without sacrificing the material? Is there any other way to bring them back to the 50 level? What is a good definition of "toughness"





RE: 4150 "toughness"
RE: 4150 "toughness"
While we await your reply to metengr's question about the application, I will add that the maximum toughness of 4150 occurs at a hardness much lower than 50 HRC and yes, it is possible to temper this grade at a higehr temperature in order to reduce the hardness from 60 HRC to ??? HRC.
RE: 4150 "toughness"
RE: 4150 "toughness"
thread330-173553
RE: 4150 "toughness"
RE: 4150 "toughness"
RE: 4150 "toughness"
RE: 4150 "toughness"
It would be good to know what the other pins we made of their hardness and what the failure was.
You will have distortion and some scaling after drawing these parts back. It may be better to centerless grind the parts after heat treating.
RE: 4150 "toughness"
The heat treat company is arguing that there testing shows a Rc of 48-52, while my measurements show 60+. Of course i can not get a copy of their test results.
I can honestly say that where i'm from it is extremely difficult to pick materials for various projects. There seams to be nobody locally to consult with, about material choice and properties. Any supplier also seems to be clueless on material properties and characteristics. Liabilty? I don't know but in the business i'm in it could be extremely helpful to at least be able to offer a customer a choice or an alternative material for a better product. Thanks for the help, i will try to get these parts annealed, hopefully all costs covered.
metengr: you mention your sources, do you have any references you reccommend? I would like to have better understanding on many of the readily available materials.
RE: 4150 "toughness"
Depending on size, quenchant used/severity, the 60HRC hardness you mention may not extend very deep into the part.
If the heat treater got 48-52 on their check either their hardness testers are way out of cal or they burned the sample trying to create a flat spot for testing. With that much discrepancy I would question the entire heat treat and inspection practice.
RE: 4150 "toughness"
ASM International offers a number of different publications that would be useful to you in material selection. Specifically on the heat treatment of steels, ASM HANDBOOK Volume 4 Heat Treating and Heat Treater's Guide: Practices and Procedures for Irons and Steels, 2nd Edition will have information on how to heat treat steels and what the resulting properties will be. Use the following link for more information:
http://w
RE: 4150 "toughness"
As dbooker630 said, sample prep could be the issue. If they wont give you the results of their internal inspection then dont accept the parts. (Some days I wish I didnt have to provide the results of some of my inspections. Hah!) Have a decent size sample from the whole batch tested at an outside A2LA Lab. Nobody wants to reject good product. Get the treater to split the cost. This wont be too expensive.
To determine the existance of a hardness profile use Vickers Micro, have a through section mounted and a profile taken. Again not that expensive and good insurance.