Investigations into the isothermal and non-isothermal hardening of alloys .2.

The second part of the paper shows the application of a model for isothermal and non-isothermal heat treatment on precipitation on hardening of AuTi1 and AlMgSi1. Both alloys show clearly at least two different mechanisms for hardening within the temperature range investigated. Considering also the age hardening at room temperature (which was nor included in the scope of the project). AlMgSi1 therefore has three ways to realise age hardening. The transition region between two mechanisms are characterised by a minimum of activation energy. A non-isothermal heating cycle is advantageous for precipitation hardening. The influence is the strongest with AuTi1 and the least with CuNi2Si (see part 1). The aluminium alloy lays in between the two other allays. In any case the effect of non-isothermal heat treatment is of practical importance.