Valve and method for producing a valve

An injection valve, comprising:

• a valve seat having a valve-seat surface;
• and
• a valve needle which extends along a closing direction, a valve-closing element being mounted on an end of the valve needle facing the valve seat, the valve-closing element being able to be moved between an open position and a closed position, the valve-closing element forming a sealing seat together with the valve-seat surface in the closed position;
• wherein the valve-closing element has at least one of:
• i) a greater core hardness than the valve-seat surface, or ii) a greater surface hardness than the valve-seat surface;
• and
• wherein the valve-closing element includes a base body material and at least one diffusion layer with nitrogen and boron diffused into the base body material, the at least one diffusion layer being produced by (i) conducting a nitrifying diffusion on the valve-closing element, the nitrifying diffusion including diffusing nitrogen into the base body material by providing a nitrogen-containing substance in at least one of:
• a gaseous state, a liquid state, or a plasma state;
• and (ii) conducting a boronizing diffusion on the valve-closing element, the boronizing diffusion including diffusing boron into the base body material by providing a boron-containing substance in at least one of:
• a gaseous state, a liquid state, or a plasma state.