The ultrafine grained (UFGed) 1050 Al plates with a thickness of 2 mm. which were produced by the accumulative roll bonding technique after five cycles. were friction stir butt welded to 2 mm thick 6061-T6 Al alloy plates at a different revolutionary pitch that varied from 0. 5 to 1. https://spencertifieders.shop/product-category/recorders-cassette-players/