@article {Gandra_J:2011, title = {Functionally graded materials produced by friction stir processing}, journal = {JOURNAL OF MATERIALS PROCESSING TECHNOLOGY}, volume = {211}, year = {2011}, note = {n/a}, month = {Jan}, pages = {1659-1668}, publisher = {TULISBON, Univ Nova Lisboa, IST UTL Inst Super Tecn, Univ Nova Lisboa}, abstract = {n/a}, author = {Gandra J and Miranda R and Vilaca P and Velhinho A and Teixeira JP} }