ANALYSIS OF CRYSTAL STRUCTURE OF THE WELDS WITH FRICTION-STIR WELDING METHOD ON THE RETREATING SIDE FOR BIMETALLIC DISIMILAR AA6061-Cu USING NEUTRON DIFFRACTION TECHNIQUES - Priyanto, Tri Hardi; Pusat Teknologi Bahan Industri Nuklir (PTBIN)- BATAN Kawasan Puspiptek, Serpong 15314, Tangerang Selatan (BATAN, 2013)