Materials transactions, JIM vol:41 issue:10 pages:1275-1281
An Al-1.0 mass%Mg2Si alloy was aged at 473 K for 36 ks. Using the same sample, resistivity (rho) measurements, tensile tests and TEM observations were carried out. The volume fraction (V-f rho) of precipitates was estimated from the decrement in resistivity due to aging. Length (lambda), diameter (d) and number density (N-P) per uni: volume of the needle-shaped precipitates were measured on TEM micrographs. Perhaps because of initiation of overaging in the present aging condition, lambda and N-P showed a wide scatter and differed significantly in two equivalent samples, independently heat treated and tested. However, proof stress and V-f rho in the two runs well coincided with each other and the volume fraction estimated from TEM micrographs (V-fTEM) matched within a factor of 2 for the two runs.