Patent ID: 7909270

Claim:
A valve assembly of an injection valve, comprising: a valve body including a central longitudinal axis, the valve body comprising a cavity forming an inner surface of the valve body, the cavity having a fluid inlet portion, and a fluid outlet portion, a valve needle axially movable in the cavity, the valve needle preventing a fluid flow through the fluid outlet portion in a closing position and releasing the fluid flow through the fluid outlet portion in further positions, a recessed area formed in at least one of the valve needle and the inner surface of the valve body, the recessed area formed adjacent at least one non-recessed area, a surface layer comprising a tungsten carbide layer and a carbon layer, the surface layer formed over one of the recessed areas but not formed over the at least one non-recessed area adjacent the recessed area, such that an outer surface of the surface layer is substantially flush with the at least one non-recessed area adjacent the recessed area.