Investigation of the dynamic properties ofaluminum targets with helium bubbles is presented.The targets were obtained by melting pure aluminumwith 0.15% wt.~(10)B powder. The solid targets were neu-tron irradiated to get homogeneous helium atoms insidethe aluminum boron 10 matrix according to the reaction ~(10)B+n→~7Li+~4He. Helium atoms further accumu-lated into bubbles by diffusion in the bulk aluminum.Shock wave experiments were performed by acceler-ating the aluminum impactor into different targets: (1)pure aluminum, (2) Al-~(10)B, and (3) Al-~(10)B with dif-ferent radii and concentrations of helium bubbles. Thespall strength was calculated and analyzed from thefree surface velocity measurements. It was found thatthe addition of ~(10)Bin pure aluminum reduces the spallstrength of the material by 25-32%. However, irradi-ated sample with helium bubbles was found to havehigher spall strength compared to samples without bub-bles. This finding was reconstructed by numerical sim-ulations. The impacted targets were collected after theimpact experiments and examined by TEM. These tar-gets were compared to TEM pictures before the impact.The number of helium atoms in the bubbles was calcu-lated from the electron energy loss spectrum (EELS).TEM comparison between the pre-impacted and theimpacted targets shows bubbles coalescence and EELSmeasurements demonstrate a reduction of the heliumatoms concentration in the bubbles from ～10~(28)m~(-3) before the impact to ～10~(27) m~(-3) after the impact.
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