Utmatting av AA6005 - Effekten av forskjellige tilstander

Abstract

The aim of this thesis is to investigate the effect of ageing, both natural and artificial, at room temperature on the fatigue properties of AA6005. Artificial ageing was done to reach a temper state of equal hardness on each side of peak hardness (T6). Preliminary testing was done on AA6005. These consisted of hardness and electric conductivity measurements after different ageing times from T1 condition and after solution heat treatment. The microstructures of the alloy was investigated by means of optical microscopy and electron microscopy to analyse the primary particles, in all temper states. The results showed that AA6005 has excellent fatigue resistance in T1 after 12 years in storage, and the fatigue resistance increases in an under-aged temper state while decreases in