the engine to provide erosion resistance the metallic blade substrate may have a coating 70 along a zone 72 exemplary ti based substrate alloys include ti u2014 6al u2014 4v ti u2014 8al u2014 1mo u2014 1v ti u2014 6al u2014 2sn u2014 4mo u2014 2zr ti u2014 6al u2014 2sn u2014 4mo u2014 6zr and ti u2014 5 5al u2014 3 5sn u2014 3zr u2014 1nb other substrates include but are not limited to stainless steels e g 17 4ph and ni base superalloys e g alloy 718 exemplary coatings include co u2014 wc nicr u2014 crc ti u2014 n and ti u2014 aln an exemplary zone 72 extends along a majority of the airfoil along the pressure and suction sides from the tip 60 to boundary 74 the exemplary boundary 74 is a radial distance s 2 from the tip exemplary s 2 is more than 50 of s along the entire chord and more than s 1 the coating may extend beyond the heaviest erosion areas and provide enhanced foreign object damage the coating 70 may have deleterious effects upon blade structural properties e g fatigue properties traditionally this has limited use of erosion coatings to areas of the blade airfoil that experience relatively low stresses according to the present invention the blade is subjected to a burnishing process to mitigate one or more of these effects and permits coating application over more of the blade airfoil the exemplary burnishing process is a low plasticity burnishing process low plasticity burnishing of aerospace parts is discussed in u s pat nos 5 826 453 6 672 838 and 6 893 225 and published application no 2005 0155203 use of such burnishing for ti based parts is also.