TRANSMISSION ELECTRON-MICROSCOPY OF (332)[113]-DEFORMATION TWIN IN TI-15V-3CR-3SN-3AL ALLOY

In a Ti-15V-3Cr-3Sn-3Al alloy, the internal structure of {332}[113] de formation twins formed by weak rolling at 77 K was studied by means of transmission electron microscopy. {332}[113] deformation twins accomp any very characteristic dislocation loops attached to the twin/matrix interface in the matrix. Inside the twin, a parallel array of stress-i nduced omega plates with a single variant are formed. It is considered that such dislocation loops are expelled from the beta twin/omega int erface into the beta matrix during the shrinkage of twins by unloading . Secondary {332}[113] twinning occurs in the primary twins by further deformation.