Gamma-ray induced modifications in a series of Pb-free Sn-1.0Ag-0.5 Cu-X solder alloys used for radiation shielding

Abstract EN

Irradiationeffects on the mechanicalproperties of a series of low Ag-content Sn–1.0Ag–0.5Cu-x solder alloys (x= 2 wt.

% In and Bi) have been investigated.

The solderalloys were exposed to γ-rays at high doses ranging from 200 to 800 kGy.The induced modifications were studied by means of several standard experimental techniques of mechanical and structural analysis of alloy materials.

An anomalousstrain softening phenomenon was observed inthese alloysinduced by high doses of γ-radiation.

It wasfound that the enhanced ductility with a slight decrease instrength occurs at a critical doseof 400 kGy.

The mechanical response of Bi-containing solders ischaracterized by increased yield and ultimate tensile strengthsas well asthe decline inductilitywith increasing dose,althoughthe Sn–1.0Ag–0.5Cu and the In-containing alloysareslightly affected athigher doses.The impact of γ-radiation has been interpreted in terms of microscopic deformation mechanisms, sincethemechanical property enhancement is caused by the cell formation and dislocation channel deformation mechanism.Such effects could assist the choice of these alloys as a new structural material design strategy in manufacturing gamma radiation shielding.