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Hollomon-Jaffe parameter



The Hollomon-Jaffe parameter, or HP, describes the effect of a heat treatment at a temperature for a certain time.

Effect

The effect of the heat treatment depends on its temperature and its time. The same effect can be achieved with a low temperature and a long holding time, or with a higher temperature and a short holding time.

Formula

In the Holloman-Jaffe parameter, This exchangability of time and temperature can be described by the following formula:

H_p = \frac {(273.15 + T)}{1000} \cdot (C + log(t))

This formula is not consistent concerning the units; the parameters must be entered in a certain manner. The argument of the logarithmic function has the unit minutes. The Hollomon parameter itself is unitless and realistic numeric values vary between 15 and 21.

 
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Hollomon-Jaffe_parameter". A list of authors is available in Wikipedia.
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