Charpy Curvefit
Charpy Curvefit
(OP)
Hi,
I was hoping to get some feedback for the following applet I put on my website
I am performing non-linear regression on Charpy data and calculating the parameters.
http ://www.nov anumeric.c om/samples .php?CalcN ame=Charpy
Any advice/direction/feature requests/constructive criticism would be greatly appreciated!
-Jeff
I was hoping to get some feedback for the following applet I put on my website
I am performing non-linear regression on Charpy data and calculating the parameters.
http
Any advice/direction/feature requests/constructive criticism would be greatly appreciated!
-Jeff





RE: Charpy Curvefit
Seems like you need four data points to do the fitting. That is a lot. Ideally I hope to just use two or three at most. Otherwise, it does not make sense to do the numerical fitting any more.
I guess the heat treatment or microstructure affect your function selection. Are you fixed with tanh function? I guess you will have to use some other functions. For example, the FCC austenite does not have the sharp drop at all (or until very low temperature).
I also suggest you to do further regression to link some of your constants with physical parameters. For example, grain size has a general positive effect on the toughness. I bet one of your parameters will have a linear relationship with grain size.
Possibly you can find one profile for each different microstructure. Further normalizing couple parameters if you can will make this idea a pretty good research paper.
RE: Charpy Curvefit
_____________________________________
"It's better to die standing than live your whole life on the knees" by Peter Mayle in his book A Good Year
RE: Charpy Curvefit
Would you mind sharing those data points with me?
Regards,
Jeff Brubaker
RE: Charpy Curvefit
Great answer !
thank you for your contribution
RE: Charpy Curvefit
Usually impact testing involves more than 2-3 data points; probably 4-5 is the norm. It is easy to find actual data on this: here is a Google search that shows tables and graphs of impact results that include discrete measurements:
http://