Steel hardenability Calculator 3

[CdotS]

I am trying to predict hardenability of different steels using 3 formulas published in ASM Handbook Vol 4: Heat Treating - page 28.

They predict steel hardness at different depths of the Jominy specimen from its chemical composition.

Is there any better way of predicting hardenability of steel?

 

[metengr]

From your description, it sounds like you are using Grossmann's method for calculating an ideal diameter based on alloying factor and grain size correlations.

This method is really time consuming, complicated, and is subject to error because the quench parameter H is typically not used, an ideal quench is assumed for simplicity.

What is it you are exactly trying to evaluate? The ASM Metals Handbook Desk Edition contains a series of end-quench curves for typical alloys (13xxH, 94BxxH, 40xxH,41xxH, 51xxH and 86xxH) showing the effects of carbon content on hardenability with a family of curves.

In addition, the ASM Metals Handbook Desk Edition describes a rather straight-forward method to determine hardenability using a Jominy equivalent cooling rate curve (see page 273 in the 2nd edition). You will have to austenitize and quench actual samples (which can be easily done using a small lab furnace and bath) to establish a baseline curve from which to evaluate changes in chemical composition and/or grain size. I have seen this method used in a production shop, and it is most reliable.

 

[CdotS]

Thanks metengr for your input.

I am trying to develop a simple mathematical (empirical eqn.) to evaluate hardenability of steel from its chemical composition. For example, I want to know how max. hardness and hardenability (can I say iso-hardness depth?) change when I reduce carbon but increase Cr, Mo or B. This preliminary finding which can be confirmed by doing Jominy tests, as you have suggested.

 

[Carburize]

Take a look at ASTM A255 and see if the information there is what you need.

 

[Rich2001]

Take a look through the Materials Algorithms Project files

http://www.msm.cam.ac.uk/map/

You might find some routines here that fit you purpose, though it is probally in Fortran.

 

[TVP]

CdotS,

SAE J406 is similar to ASTM 255, and either one should contain the information that you need.