Transition metal nitride, separator for fuel cells, fuel cell stack, fuel cell vehicle, method of manufacturing transition metal nitride, and method of manufacturing separator for fuel cells
AssigneeNissan Motor Co., Ltd.
InventorsNoriko Uchiyama, Nobutaka Chiba, Makoto Kano
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Abstract
A transition metal nitride is obtained by a nitriding treatment of a surface of a base material including a transition metal or an alloy of the transition metal, and the transition metal nitride has a crystal structure of an M4N type and a crystal structure of an ε-M2˜3N type, and is formed over a whole area of the surface of the base material and continuously in a depth direction from the surface.
Claims26
A transition metal nitride obtained by a nitriding treatment of a surface of a base material including a transition metal or an alloy of the transition metal, wherein
- the transition metal nitride has a crystal structure of an M4N type and a crystal structure of an ε-M2˜3N type, and is formed over a whole area of the surface of the base material and continuously in a depth direction from the surface.
The separator for fuel cells as claimed in 17, wherein the base material comprises a stainless steel containing transition metal elements selected from among Fe, Cr, Ni, and Mo, having Fe as a principal component, meeting formulas (8) to (10) below:
- 18 wt %≦Cr≦26 wt % (8)
- 11 wt %≦Ni≦21 wt % (9)
- 0 wt %≦Mo≦2 wt % (10)
The separator for fuel cells as claimed in 17, meeting formulas (11) to (13) below:
- 24 wt %≦Cr≦26 wt % (11)
- 14 wt %≦Ni≦20 wt % (12)
- 0 wt %≦Mo≦1 wt % (13)
A method of manufacturing a transition metal nitride to be formed on a surface of a base material comprising a transition metal or an alloy of the transition metal, by a plasma nitriding, comprising
- forming, by the plasma nitriding, crystal structures of an M4N type and crystal structures of an ε-M2˜3N type, over a whole area of the surface of the base material and in a depth direction from the surface.
A method of manufacturing a separator for fuel cells, comprising plasma nitriding a surface of a base material comprising a transition metal or an alloy of the transition metal, and forming, by the plasma nitriding, a nitrided layer having crystal structures of an M4N type and crystal structures of an ε-M2˜3N type, over a whole area of the surface and in a depth direction from the surface.
Dependencies are inferred from the claim text.