REDUCTION OF THE EVAPORATION RATE OUT OF PLATINUM AND Pt ALLOYS
Methods for reducing the evaporation rate of platinum and Pt alloys upon their use at high temperatures >1,200° C. in an oxidizing atmosphere include the steps: (A) providing a component made of platinum or a platinum alloy; (B) wrapping the outer surface of the component with a flexible bandage having open porosity and provided with an oxide ceramic material and/or a glass-forming material; (C) using the component at operating temperatures >1,200° C. Methods for scavenging noble metal oxides evaporating or sublimating from the surface of platinum or Pt alloys include: (A) providing a component made of platinum or a platinum alloy; (B) wrapping the outer surface of the component with a flexible bandage having open porosity; and (C) using the component at operating temperatures >1,200° C. Correspondingly wrapped components are also provided.
1 .- 15 . (canceled)
16 . A component made of platinum or a Pt alloy, wherein the component is subjected to an oxidizing atmosphere at temperatures >1,200° C., the component being wrapped with a flexible bandage having open porosity, wherein the bandage is provided with one of (a) a glass-forming material and (b) an oxide ceramic material and a glass-forming material.
17 . The component according to claim 16 , wherein the bandage comprises a high-melting oxide material.
18 . The component according to claim 16 , wherein the bandage comprises Al 2 O 3 .
19 . The component according to claim 16 , wherein the bandage comprises a noble metal gauze or fleece.
20 . The component according to claim 19 , wherein the gauze or fleece comprises platinum or platinum-rhodium.
21 . The component according to claim 16 , wherein the glass-forming material is selected from the group consisting of silicon dioxide, diboric trioxide, diphosphorus pentoxide, germanium dioxide, and diantimony pentoxide.
22 . The component according to claim 16 , wherein the oxide ceramic material is selected from the group consisting of Al 2 O 3 ; ZrO 2 ; SiO 2 .ZrO 2 ; SiO 2 ; HfO 2 ; CaO; MgO; and rare earth metal oxides.
23 . A method for scavenging noble metal oxides evaporating or sublimating from a surface of platinum or Pt alloys, the method comprising steps of:
1. providing a component made of platinum or a platinum alloy;
2. wrapping an outer surface of the component with a flexible bandage having open porosity, wherein the bandage is provided with one of (i) a glass-forming material and (ii) an oxide ceramic material and a glass-forming material; and
(c) using the wrapped component at operating temperatures >1,200° C.
24 . The method according to claim 23 , wherein the bandage comprises a high-melting oxide material.
25 . The method according to claim 24 , wherein the high-melting oxide material is selected from the group consisting of Al 2 O 3 ; mullite; hafnium oxide; lanthanum oxide; ZrO 2 ; ZrO 2 .SiO 2 ; SiO 2 ; rare earth oxides; and mixtures of said oxides.
26 . The method according to claim 23 , wherein the bandage comprises Al 2 O 3 .
27 . The method according to claim 23 , wherein the bandage comprises a noble metal gauze or fleece.
28 . The method according to claim 27 , wherein the gauze or fleece comprises platinum or platinum-rhodium.
29 . The method according to claim 23 , wherein the glass-forming material is selected from the group consisting of silicon dioxide, boric oxide, phosphorus pentoxide, germanium dioxide, and diantimony pentoxide.
30 . A method for reducing the evaporation rate of platinum and Pt alloys upon their use at temperatures >1,200° C. in an oxidizing atmosphere, the method comprising steps of:
A providing a component made of platinum or a platinum alloy;
B wrapping an outside of the component with a flexible bandage having open porosity provided with one of (i) a glass-forming material and (ii) an oxide ceramic material and a glass-forming material; and
C using the wrapped component at operating temperatures >1,200° C.
31 . The method according to claim 30 , wherein the bandage comprises a high-melting oxide material.
32 . The method according to claim 31 , wherein the high-melting oxide material is selected from the group consisting of Al 2 O 3 ; mullite; hafnium oxide; lanthanum oxide; ZrO 2 ; ZrO 2 .SiO 2 ; SiO 2 ; rare earth oxides; and mixtures of said oxides.
33 . The method according to claim 30 , wherein the bandage comprises Al 2 O 3 .
34 . The method according to claim 30 , wherein the bandage comprises a noble metal gauze or fleece.
35 . The method according to claim 34 , wherein the gauze or fleece comprises platinum or platinum-rhodium.
36 . The method according to claim 30 , wherein the glass-forming material is selected from the group consisting of silicon dioxide, boric oxide, phosphorus pentoxide, germanium dioxide, and diantimony pentoxide.