Low alloyed 23-04, free molybdenum, duplex stainless steels are very attractive. The combination of high mechanical properties and good corrosion resistance, make the alloy very interesting when compared with classical 304 L or 316 L. A Cu enriched version for 23-04: UR 35 N Cu has been developed during these last years, with the aim to improve machinability. Results present in the paper show that improvement of machinability is obtained without detrimental effect on microstructure or corrosion performances. The interest of UR 35 NCu for applications where abrasion corrosion is concerned is underlined.