A vibration-resistant, flexible metallic seal for use in an electrohydraulic servo valve (EHSV), the EHSV comprising an armature, an armature support comprising a base, and a flapper, the seal surrounding a portion of the flapper, the seal having a first end, a second end, a thickness along a length of the seal between the first end and the second end, the thickness being defined between first and second outer surfaces of the seal, and one or a plurality of convolutions between the first end and the second end, the first end disposed between and hermetically connected to the flapper and the armature, the second end disposed within the first opening and hermetically connected to the base, wherein the seal comprises: a non-porous metal that comprises a first fraction of the thickness; a porous metal comprising a plurality of pores that comprises a second fraction of the thickness; and an elastomeric material encompassed by the pores of the second fraction of the thickness, wherein the second fraction comprises one or both of the first and second outer surfaces of the seal.