Positron Lifetime in Deformed AISiio.9Mgo.17Sro.oe Alloys

摘要

Positron annihilation lifetime spectroscopy (PALS) is one of the nuclear techniques used in material science. (PALT) measurements are used to study the behaviour of the defect concentration in a set of AlSi10.9Mgo.17Sro.06 alloys. It has been shown that positrons can become trapped at imperfect locations in solids, and that their mean lifetime can be influenced by changes in the concentration of such defects. No changes have been observed in the mean lifetime values following saturation of tile defect concentration. The mean lifetime and trapping rates were studied for samples deformed up to 34.9 %. The concentrations of defects range vary from 5.194xlO15 to 1.934×10~18 cm~(-3) for thickness reductions of 2.2 to 34.9 %. The range of the dislocation density varies from 1.465x 108 to 5.454 ×10~10cm/cm~3 over the same range of deformations.