Fuel injector

A fuel injector for an internal combustion engine, the fuel injector comprising:

• an injection nozzle comprising a nozzle body provided with a nozzle bore;
• a valve needle assembly received within the nozzle bore and including a valve needle engageable with a seat region to control fuel delivery through at least one outlet of the injection nozzle;
• a first actuator arrangement and a second actuator arrangement, each actuator arrangement being operable to apply an opening force to an engagement region of the valve needle assembly to cause an opening movement thereof;
• wherein the first actuator arrangement comprises a first conductive coil mounted concentrically on a first body and a first armature configured to apply the opening force to the valve needle assembly, wherein the first armature is slidable with respect to the engagement region, and wherein the first armature and the engagement region are separated by a clearance when the valve needle is engaged with the seat region;
• and
• wherein the first body comprises a first, radially inner region and a second region disposed radially between the first coil and the first region,
• wherein a magnetic permeability value of the first region is higher than a magnetic permeability value of the second region, in use, and
• wherein the second actuator arrangement comprises a second conductive coil mounted on a second body and a second armature configured to apply the opening force to the valve needle assembly, and
• wherein the second body comprises a third, radially inner region and a fourth region disposed radially between the second coil and the third region,
• wherein a magnetic permeability value of the third region is higher than a magnetic permeability value of the fourth region, in use.