Hydrogen storage metal alloy and production thereof
A process for producing hydrogen storage metal alloys having a body-centered cubic structure-type main phase enabling the adsorption and desorption of hydrogen is provided which comprises the steps of: (1) melting a starting alloy brought to a predetermined element ratio to form a uniform heat (melting step), (2) keeping the homogenized alloy heat at a temperature within a range just below the melting point of the alloy for a predetermined time (heat treatment), and (3) rapidly cooling the alloy after the heat treatment (quenching step).
1 . A hydrogen storage metal alloy which has
having a main phase with a body-centered cubic structure enabling the adsorption and desorption of hydrogen, said alloy having
a composition of the following general composition formula:
Ti (100-a-0.4b) Cr (a-0.6b) M b
wherein M is vanadium (V), provided that 20≦a (at %)≦80, and 0≦b (at %)≦10.
2 . The hydrogen storage metal alloy according to claim 1 wherein a level of the constituent element V contained in the alloy is within a range of 6±2 at %.
3 . A hydrogen storage metal alloy
having a main phase with a body-centered cubic structure enabling the adsorption and desorption of hydrogen, said alloy having
a composition of the following general composition formula:
Ti (100-a-0.4b) Cr (a-0.6b) M b
wherein M is at least a member selected from molybdenum (Mo) and tungsten (W), provided that 20≦a (at %)≦80 and 0≦b (at %)<5.
4 . The hydrogen storage metal alloy according to claim 3 wherein a level each of the constituent element Mo and/or W contained in the alloy is within a range of 3±1.5 at %.
5 . A hydrogen storage metal alloy having
a main phase with a body-centered cubic structure the adsorption and desorption of hydrogen, said alloy having
a composition of the following general composition formula:
Ti (100-a-0.4b) Cr (a-0.6b) V (b-c) M c
wherein M is at least a member selected from molybdenum (Mo) and tungsten (W), provided that 20≦a (at %)≦80, 0≦b (at %)≦10, and 0≦c (at %)<5.
6 . The hydrogen storage metal alloy according to claim 1 wherein the element X is admixed at its atom % concentration, d (at %), ranging within 0≦d (at %)≦20, the atomic radius of which is larger than that of Cr but smaller than that of Ti.
7 . The hydrogen storage metal alloy according to claim 6 wherein the element X is at least one or more members selected from the group consisting of Al, Ge, Ga, Si, Au and Pt.
8 . The hydrogen storage metal alloy according to claim 1 wherein the element T is admixed at its atom % concentration, e (at %), ranging within 0≦e (at %)≦10 and includes at least one or more members selected from the group consisting of Nb, Ta, Mn, Fe, Al, B, C, Co, Cu, Ga, Ge, a lanthanoid metal), N, Ni, P, and Si.
9 - 12 . (canceled)
13 . The hydrogen storage metal alloy according to claim 3 wherein the element X is admixed at its atom % concentration, d (at %), ranging within 0≦d (at %)≦20, the atomic radius of which is larger than that of Cr but smaller than that of Ti.
14 . The hydrogen storage metal alloy according to claim 13 wherein the element X is at least one or more members selected from the group consisting of Al, Ge, Ga, Si, Au and Pt.
15 . The hydrogen storage metal alloy according to claim 3 wherein the element T is admixed at its atom % concentration, e (at %), ranging within 0≦e (at %)≦10 and includes at least one or more members selected from the group consisting of Nb, Ta, Mn, Fe, Al, B, C, Co, Cu, Ga, Ge, a lanthanoid metal), N, Ni, P, and Si.
16 . The hydrogen storage metal alloy according to claim 5 wherein the element X is admixed at its atom % concentration, d (at %), ranging within 0≦d (at %)≦20, the atomic radius of which is larger than that of Cr but smaller than that of Ti.
17 . The hydrogen storage metal alloy according to claim 16 wherein the element X is at least one or more members selected from the group consisting of Al, Ge, Ga, Si, Au and Pt.
18 . The hydrogen storage metal alloy according to claim 5 wherein the element T is admixed at its atom % concentration, e (at %), ranging within 0≦e (at %)≦10 and includes at least one or more members selected from the group consisting of Nb, Ta, Mn, Fe, Al, B, C, Co, Cu, Ga, Ge, a lanthanoid metal), N, Ni, P, and Si.
19 . The hydrogen storage metal alloy according to claim 1 wherein the structure comprises a mono-phase structure.
20 . The hydrogen storage metal alloy according to claim 3 wherein the structure comprises a mono-phase structure.
21 . The hydrogen storage metal alloy according to claim 5 wherein the structure comprises a mono-phase structure.
22 . A hydrogen storage metal alloy having a main phase with body-centered cubic structure enabling the adsorption and desorption of hydrogen, said alloy having a composition of the following general composition formula:
Ti (100-a-0.4b-n1[d+e]) Cr (a-0.6b-n2[d+e]) V (b-n3[d+e]) X d T e (I)
wherein
X is at least one or more other elements selected from the group consisting of Al, Ge, Ga, Si, Au and Pt,
T is at least one or more other elements selected from the group consisting of Nb, Ta, Mn, Fe, Al, B, C, Co, Cu, Ga, Ge, a lanthanoid metal, N, Ni, P, and Si, and
20≦a (at %)≦80;
0≦b (at %)≦10;
0≦d (at %)≦20;
0≦e (at %)≦10 and
n1+n2+n3=1, or
Ti (100-a-0.4b-n1[d+e]) Cr (a-0.6b-n2[d+e]) M (b-n3[d+e]) X d T e (II)
wherein
M is at least a member selected from molybdenum (Mo) and tungsten (W),
X is at least one or more other elements elected from the group consisting of Al, Ge, Ga, Si, Au and Pt,
T is at least one or more elements selected from the group consisting of Nb, Ta, Mn, Fo, Al, B, C, Co, Cu, Ga, Ge, a lanthanoid metal, N, Ni, P, and Si, and
20≦a (at %)≦80;
0≦b (at %)≦5;
0≦d (at %)≦20;
0≦e (at %)≦10 and
n1+n2+n3=1, or
Ti (100-a-0.4b-n1[d+e]) Cr (a-0.6b-n2[d+e]) V (b-n3[d+e]) M (c-n4[d+e]) X d T e (III)
wherein
M is at least a member selected from molybdenum (Mo) and tungsten (W),
X is at least one or more other elements selected from the group consisting of Al, Ge, Ga, Si, Au and Pt,
T is at least one or more other elements selected from the group consisting of Nb, Ta, Mn, Fe, Al, B, C, Co, Cu, Ga, Ge, a lanthanoid metal, N, Ni, P, and Si, and
20≦a (at %)≦80;
0≦b (at %)≦10;
0≦c (at %)≦5
0≦d (at %)≦20
0≦e (at %)≦10 and
n1+n2+n3+n4=1.
23 . The hydrogen storage metal alloy according to claim 22 wherein the elements of the alloy correspond to the composition of the following general composition formula:
Ti (100-a-0.4b-n1[d+e]) Cr (a-0.6b-n2[d+e]) V (b-n3[d+e]) X d T e
wherein
X is at least one or more other elements selected from the group consisting of Al, Ge, Ga, Si, Au and Pt,
T is at least one or more other elements selected from the group consisting of Nb, Ta, Mn, Fe, Al, B, C, Co, Cu, Ga, Ge, a lanthanoid metal, N, Ni, P, and Si, and
20≦a (at %)≦80;
b is within a range of 6±2 (at %);
0≦d (at %)≦20;
0≦e (at %)≦10 and
n1+n2+n3=1.
24 . The hydrogen storage metal alloy according to claim 22 , wherein the structure comprises a mono-phase structure.