1. A catalyst supporting honeycomb comprising:
a pillar-shaped honeycomb structure having a plurality of cells formed in parallel with one another in a longitudinal direction with a cell wall interposed therebetween; and
catalyst particles supported on the honeycomb structure,
said honeycomb structure having an integral honeycomb structure comprising a single member obtained by extrusion-molding a mixture comprising inorganic fibers and an inorganic material, said inorganic material melting at a temperature of a heat-resistant temperature of the inorganic fibers or lower, a porosity of said cell wall being about 70% or more,
said catalyst particles being configured by an oxide catalyst having an average particle diameter of at least about 0.05 \u03bcm and at most about 1.00 \u03bcm,
wherein said inorganic fibers are fixed to each other through the inorganic material at intersection portions of the inorganic fibers, and
wherein said inorganic material is present locally at said intersection portions of the inorganic fibers.
2. The catalyst supporting honeycomb according to claim 1,
wherein
either of two end portions of each of said cells is sealed.
3. The catalyst supporting honeycomb according to claim 1,
wherein
said honeycomb structure is formed by a plurality of lamination members laminated with one another in a longitudinal direction, and
said lamination members are laminated so that the cells of each lamination member are aligned with the cells of the other lamination members.
4. The catalyst supporting honeycomb according to claim 1,
wherein
said oxide catalyst is at least one member selected from the group consisting of CeO2, ZrO2, FeO2, Fe2O3, CuO, CuO2, Mn2O3, MnO, K2O, and a composite oxide represented by a composition formula AnB1-nCO3 in which A represents La, Nd, Sm, Eu, Gd or Y; B represents an alkali metal or an alkali earth metal; and C represents Mn, Co, Fe or Ni.
5. A catalyst supporting honeycomb comprising:
a pillar-shaped honeycomb structure having a plurality of cells formed in parallel with one another in a longitudinal direction with a cell wall interposed therebetween, said honeycomb structure having an integral honeycomb structure comprising a single member obtained by extrusion-molding a mixture comprising inorganic fibers and an inorganic material, said cell wall comprising inorganic fibers and an inorganic material, said inorganic material melting at a temperature of a heat-resistant temperature of the inorganic fibers or lower, a porosity of said cell wall being about 70% or more, and
oxide catalyst particles supported on the cell wall, said oxide catalyst particles being supported by flowing a gas containing a dispersed solution of a precursor of the oxide catalyst into the honeycomb structure, wherein said oxide catalyst particles have an average particle diameter of at least about 0.05 \u03bcm and at most about 1.00 \u03bcm,
wherein said inorganic fibers are fixed to each other through the inorganic material at intersection portions of the inorganic fibers, and
wherein said inorganic material is present locally at said intersection portions of the inorganic fibers.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A process for resurfacing a monocrystalline or directionally solidified metallic piece having a length, a width and a thickness (Ws), wherein said thickness, when measured across a side wall of said metallic piece, varies between 0.2 and 2 mm along said width, said process comprising:
applying coaxially a laser beam and a flux of metallic powder to said side wall of the metallic piece and along said width, wherein the metallic powder is of a same nature as that of the metallic piece, to produce at least one layer of metal, monocrystalline or directionally solidified, on said side wall and along said width of the metallic piece,
emitting the laser beam at a power \u201cP\u201d and moving said laser beam along the metallic piece at a speed \u201cv\u201d, and
adapting a Pv ratio as a function of said thickness (Ws) of said metallic piece as said laser beam moves along said side wall of said metallic piece at said speed, wherein said adapting of said Pv ratio is performed as follows:
for a thickness Ws between 0.2 and 0.6 mm, maintaining said Pv ratio between two portions of increasing Pv vs Ws curves, one taking values ranging from 0.12 to 0.58 Wmm-1, the other taking values ranging from 0.25 to 0.84 Wmm-1;
for a thickness Ws between 0.6 and 0.8 mm, maintaining said Pv ratio between two portions of increasing Pv vs Ws curves, one taking values ranging from 0.58 to 0.83 Wmm-1, the other taking values ranging from 0.84 to 1.42 Wmm-1;
for a thickness Ws between 0.8 and 1 mm, maintaining said Pv ratio between two portions of increasing Pv vs Ws curves, one taking values ranging from 0.83 to 1.08 Wmm-1, the other taking values ranging from 1.42 to 2.05 Wmm-1;
for a thickness Ws between 1 and 1.2 mm, maintaining said Pv ratio between two portions of increasing Pv vs Ws curves, one taking values ranging from 1.08 to 1.27 Wmm-1, the other taking values ranging from 2.05 to 2.34 Wmm-1;
for a thickness Ws between 1.2 and 1.4 mm, maintaining said Pv ratio between two portions of increasing Pv vs Ws curves, one taking values ranging from 1.27 to 1.33 Wmm-1, the other taking values ranging from 2.34 to 2.48 Wmm-1;
for a thickness Ws between 1.4 and 2 mm, maintaining said Pv ratio between two portions of increasing Pv vs Ws curves, a constant one equal to 1.33 Wmm-1, the other taking values ranging from 2.48 to 2.75 Wmm-1,
wherein the laser beam and the metallic powder are applied by a projection nozzle, and wherein said adapting of said Pv ratio is performed automatically via a program that includes predetermined information about an evolution of said thickness (Ws) along said side wall and that automatically controls said Pv ratio as a function of a position of said nozzle along said side wall of the metallic piece.
2. The process as claimed in claim 1, wherein the portions of Pv vs Ws curves are portions of straight lines.
3. The process as claimed in claim 1, further comprising pre-heating the piece prior to applying the flux of powder.
4. The process as claimed in claim 3, wherein the pre-heating is carried out by laser beam.
5. The process as claimed in claim 1, wherein applying the flux of powder is carried out without pre-heating of the piece.
6. The process as claimed in claim 1, further comprising fabricating successively several layers of metal on top of each other, wherein the energy applied along the metallic piece to all the layers is the same.
7. The process as claimed in claim 6, wherein a same Pv ratio is maintained for the layers to which the same energy is applied.
8. The process as claimed in claim 1, further comprising producing successively several layers of metal on top of each other, wherein the energy of a first layer is less than the energy of subsequent layers.
9. The process as claimed in claim 8, wherein a same Pv ratio is maintained for the layers to which the same energy is applied.
10. The process as claimed in claim 1, wherein the metallic piece and the metallic powder comprise a monocrystalline alloy known as AM1.
11. The process as claimed in claim 1, wherein the laser beam is a YAG laser beam.
12. The process as claimed in claim 1, wherein the laser beam and the metallic powder are applied by a projection nozzle, comprising a truncated end portion which comprises a central bore for passage of the laser beam and channels, extending in the generation wall of its truncated end, for supplying the powder.
13. The process as claimed in claim 1, wherein the metallic piece is a gas turbine motor blade.
14. The process as claimed in claim 1, wherein said adapting of said Pv ratio is performed as follows:
for a thickness Ws between 0.2 and 0.6 mm, maintaining said Pv ratio between two portions of increasing Pv vs Ws curves, one taking values ranging from 0.125 to 0.58 Wmm-1, the other taking values ranging from 0.25 to 0.833 Wmm-1,
for a thickness Ws between 0.6 and 0.8 mm, maintaining said Pv ratio between two portions of increasing Pv vs Ws curves, one taking values ranging from 0.583 to 0.83 Wmm-1, the other taking values ranging from 0.84 to 1.417 Wmm-1,
for a thickness Ws between 0.8 and 1 mm, maintaining said Pv ratio between two portions of increasing Pv vs Ws curves, one taking values ranging from 0.833, to 1.08 Wmm-1, the other taking values ranging from 1.42, to 2.042 Wmm-1;
for a thickness Ws between 1 and 1.2 mm, maintaining said Pv ratio between two portions of increasing Pv vs Ws curves, one taking values ranging from 1.083, to 1.27 Wmm-1, the other taking values ranging from 2.05 to 2.333 Wmm-1,
for a thickness Ws between 1.2 and 1.4 mm, maintaining said Pv ratio between two portions of increasing Pv vs Ws curves, one taking values ranging from 1.271 to 1.33 Wmm-1, the other taking values ranging from 2.34 to 2.479 Wmm-1,
for a thickness Ws between 1.4 and 2 mm, maintaining said Pv ratio between two portions of increasing Pv vs Ws curves, a constant one equal to 1.333 Wmm-1, the other taking values ranging from 2.48 to 2.75 Wmm-1.
15. A process for resurfacing a monocrystalline or directionally solidified metallic piece having a length, a width and a thickness (Ws), wherein said thickness, when measured across a side wall of said metallic piece, varies between 0.2 and 2 mm along said width, said process comprising:
applying coaxially a laser beam and a flux of metallic powder to said side wall of the metallic piece and along said width, wherein the metallic powder is of a same nature as that of the metallic piece, to produce at least one layer of metal, monocrystalline or directionally solidified, on said side wall and along said width of the metallic piece,
emitting the laser beam at a power \u201cP\u201d and moving said laser beam along the metallic piece at a speed \u201cv\u201d, and
adapting a Pv ratio as a function of said thickness (Ws) of said metallic piece as said laser beam moves along said side wall of said metallic piece at said speed, wherein said adapting of said Pv ratio is performed as follows:
for a thickness Ws between 0.2 and 0.6 mm, maintaining said Pv ratio between two portions of increasing Pv vs Ws curves, one taking values ranging from 0.12 to 0.58 Wmm-1, the other taking values ranging from 0.25 to 0.84 Wmm-1;
for a thickness Ws between 0.6 and 0.8 mm, maintaining said Pv ratio between two portions of increasing Pv vs Ws curves, one taking values ranging from 0.58 to 0.83 Wmm-1, the other taking values ranging from 0.84 to 1.42 Wmm-1;
for a thickness Ws between 0.8 and 1 mm, maintaining said Pv ratio between two portions of increasing Pv vs Ws curves, one taking values ranging from 0.83 to 1.08 Wmm-1, the other taking values ranging from 1.42 to 2.05 Wmm-1;
for a thickness Ws between 1 and 1.2 mm, maintaining said Pv ratio between two portions of increasing Pv vs Ws curves, one taking values ranging from 1.08 to 1.27 Wmm-1, the other taking values ranging from 2.05 to 2.34 Wmm-1;
for a thickness Ws between 1.2 and 1.4 mm, maintaining said Pv ratio between two portions of increasing Pv vs Ws curves, one taking values ranging from 1.27 to 1.33 Wmm-1, the other taking values ranging from 2.34 to 2.48 Wmm-1;
for a thickness Ws between 1.4 and 2 mm, maintaining said Pv ratio between two portions of increasing Pv vs Ws curves, a constant one equal to 1.33 Wmm-1, the other taking values ranging from 2.48 to 2.75 Wmm-1,
wherein said adapting of said Pv ratio is performed by an auto-regulator that controls said Pv ratio in real time as a function of data obtained by measuring in real time a property that depends on said thickness (Ws) at any given point along said side wall of said metallic piece.
16. The process as claimed in claim 15, wherein said property is luminosity and said measuring is performed by a photodiode connected to said auto-regulator.