A mechanical end face seal for sealing between a housing and a relatively rotating shaft which seal includes a pair of relatively rotating annular rings having seal faces in sealing contact with each other to define a seal interface, with one of the rings adapted to be secured to said shaft for rotation therewith, and the other fixed relative to the housing and one being axially movable toward the other. A generally annular flexible metal diaphragm secured between the axially movable ring and either the housing or shaft includes a generally radial disc-like central portion which defines a plurality of annular convolutions formed by protrusions extending in opposite axial directions. The diaphragm is pressed onto a cylindrical surface on the ring at about the center of mass of the ring. The surface includes a coating of a compound including PTFE, grit and a binder. In one form, the seal utilizes a second seal ring pressed into fluid tight relation with its associated carrier at about the center of mass of the ring. In anotherform, a seal ring is provided which is secured to its associated carrier in fluid tight relation utilizing welding techniques. The associated methods are disclosed.