STUDY OF THE SURFACE INTEGRITY IN A SUPER DUPLEX STAINLESS STEEL AFTER TURNING Éd Claudio Bordinassi Carlos Oscar Correa de Almeida Filho ecb@maua.br cocaf@maua.br Escola de Engenharia Mauá, Instituto Mauá de Tecnologia Praça Mauá, 01 – 09580-900 – São Caetano do Sul - SP – Brasil Sergio Delijaicov sergiode@fei.edu.br Departamento de Engenharia de Mecânica, Centro Universitário da FEI Av. Humberto de Alencar Castelo Branco, 3972 – 09850-901 – São Bernardo do Campo - SP – Brasil Gilmar Ferreira Batalha Marco Stipkovic Filho gfbatalh@usp.br kovic@osite.br Dept. de Engenharia de Mecatrônica e de Sistemas Mecânicos, Escola Politécnica da USP Av. Prof. Mello Moraes, 2231 - 05508-900 – Cidade Universitária – São Paulo - SP – Brasil Abstract. The purpose of this paper was to study the main effects of the turning in the surface integrity of the duplex stainless steel ASTM A890-Gr6A.The focus of the work was the finishing operations and a complete factorial planning was used, with 2 levels and 5 factors. The tests were conducted on a turning center with carbide tools and the main entrances variables were: tool material class, feed rate, cutting depth, and cutting speed. The analyzed answers were: microstructure analysis, surface roughness, cutting force measurements and the micro-hardness variation. The results showed that was not possible to find microstructural changes even when the bigger cutting parameters were used. The other answers were correlated with the cutting parameters and a good selection was founded to the best surface integrity generation, that means, that the smaller feed rate, the smaller cutting speed and the bigger cutting depth provides the best combination of the best roughness and the micro-hardness values. Keywords: Manufacturing and processing, machining, turning, super duplex stainless steel and surface integrity.