Commercial alloys are continuously developed to improve their performance. Therefore it is
useful to establish new optimisation software, which could be used in development of new
materials or in materials selection. In the first part of the thesis, mechanical and technological
properties, which are of importance in materials selection in mechanical design, are investigated.
Two types of materials are analysed for the mechanical properties, aluminium alloys and
stainless steels but only aluminium alloys for the technological properties.
Thermodynamic analysis has been used to evaluate the effect of the microstructure. Solid
solution hardening has been successfully modelled for both aluminium alloys and stainless steels
following the theories by Labusch and Nabarro. The precipitation hardening is most dominant
for the hardenable aluminium alloys, but the non-hardenable alloys also increase their strength
from precipitation hardening. The non-hardenable alloys are divided into different tempers,
which differ in the amount of strain hardening. This has also been modelled successfully.
Combining these fundamental results with multiple regressions, models for mechanical and
technological properties have been created. Separate models are developed for wrought
aluminium alloys and stainless steels. For the aluminium alloys these include the solid solution
hardening and the precipitation hardening. For the stainless steels, the thickness, nitrogen content
and ferrite content are included together with the solid solution hardening.INTRODUCTION:For the strengthening of suitable aluminum alloys, a heat treatment known as age hardening is sometimes performed. Strength is thereby increased by the mechanism of particle strengthening. The particles, which cause the strengthening, have a typical size in the nanometer-scale Age hardening contains three steps: solution annealing, quenching and aging. During solution annealing, the relevant...