Claims
- 1. Method for the production of open-pored sintered bodies composed of glass, having a large open-pore volume, high flexural tensile strength, predetermined pore sizes and high flow velocities for fluids and gases, by means of sintering a glass-salt mixture followed by washing out the salt, including the steps of:
- producing a parent granular material composed of fine grained glass powder, coarse grained salt powder, the salt having a melting point higher than the glass sintering temperature to prevent the salt from combining with the glass material, said salt being soluble in liquids that do not dissolve the glass, and a bonding material, and to the resulting granulated material admixing 5 to 20 weight percent, with respect to said granulated material, of fine grained glass powder, subjecting the resulting mass to a molding procedure to produce a molded body and sintering the body by heating to the sintering temperature of the glass, and afterwards washing out the salt from the sintered glass.
- 2. The method according to claim 1 wherein said salt is K.sub.2 SO.sub.4.
- 3. The method according to any one of claims 1 or 2 wherein the grain size of the fine-grained glass powder which is admixed to said granular material includes grains of any size up to 100 .mu.m.
- 4. The method according to any of claims 1 or 2 wherein the grain size of the fine-grained glass powder which is admixed to said granular material includes grains of any size up to 40 .mu.m.
- 5. Open-pored sintered bodies according to any one of claims 1 or 2 having flexural tensile strengths of 7 to 12 N/mm.sup.2, pore volumes of 60% to 75% and pore diameters in the range of 30 to 40 .mu.m.
- 6. Open-pored sintered bodies according to any one of claims 1 or 2 having flexural strengths of 7 to 12 N/mm.sup.2, pore volumes of 60% to 75% and pore diameters in the range of 80 to 100 .mu.m.
- 7. Open-pored sintered bodies according to any one of claims 1 or 2 having flexural tensile strengths of 7 to 12 N/mm.sup.2, pore volumes of 60% to 75% and pore diameters in the range of 110 to 150 .mu.m.
- 8. Open-pored sintered bodies according to any one of claims 1 or 2 having flexural tensile strengths of 7 to 12 N/mm.sup.2, pore volumes of 60% to 75% and pore diameters in the range of 10 to 15 .mu.m.
- 9. A method of producing open-pored sintered bodies comprising:
- mixing vigorously 75% by weight of K.sub.2 SO.sub.4 having grains of any size up to and including 40 .mu.m, 25% by weight of borosilicate Duran glass powder type No. 8330, grain size of any size up to and including 20 .mu.m, and 100 ml of a 30% aqueous polyethylene glycol solution per kilogram of mixture,
- filtering and drying the mixture to a granulate of 200 to 300 .mu.m grain size parent material,
- mixing into the granular material 10% by weight, with respect to the parent granular material, of pure glass powder of the above-mentioned type having grains of any size up to and including 40 .mu.m in the form of a granulate having grains whose size is in the range of 200 to 300 .mu.m,
- drying the mixture and compressing the mixture with a surface pressure of at least 1000 bar to form blanks, and
- sintering the compressed blanks at about 860.degree. C. and then, washing out the K.sub.2 SO.sub.4.
- 10. A method of producing open-pored sintered bodies, comprising:
- mixing vigorously 75% by weight of K.sub.2 SO.sub.4 having grains of any size up to and including 40 .mu.m, 25% by weight of borosilicate Duran glass powder type No. 8330 having grains of any size up to and including 20 .mu.m and 100 ml of 30% aqueous polyethylene glycol solution per kilogram of mixture to yield a parent granulate material,
- adding and mixing 10% by weight, relative to the parent granulate material of glass powder of the above-mentioned type having grains of any size up to and including 40 .mu.m,
- filtering and drying the resulting mixture,
- compressing the mixture with a surface pressure of at least 1000 bar to form blanks,
- sintering the blanks at about 860.degree. C., and
- washing out the K.sub.2 SO.sub.4.
- 11. A method of producing open-pored sintered bodies, comprising:
- mixing vigorously 55% by weight of K.sub.2 SO.sub.4 having grains whose size is in the range of 100 to 200 .mu.m and 45% by weight of borosilicate Duran glass powder type No. 8330 having grain size in the range of 40 to 60 .mu.m, and 100 ml of aqueous 30% polyethylene glycol solution per kilogram of the mixture to yield a parent granulate material,
- adding and mixing 10% by weight, with respect to the parent granulate material, of borosilicate Duran glass powder type No. 8330 having grain sizes of any size up to 40 .mu.m,
- filtering and drying the resulting mixture,
- compressing the mixture with a surface pressure of at least 1000 bar to form blanks,
- sintering the blanks at about 860.degree. C., and
- washing out the K.sub.2 SO.sub.4.
- 12. A method of producing open-pored sintered bodies comprising:
- mixing vigorously 55% by weight of K.sub.2 SO.sub.4 powder having grain sizes in the range of 100 to 200 .mu.m, 45% by weight of borosilicate Duran glass powder type No. 8330 having grain sizes up to and including 20 .mu.m, and 100 ml of 30% aqueous polyethylene glycol solution per kilogram of the mixture to yield a parent granular material,
- adding and mixing 10% by weight, relative to the parent granular material, of borosilicate Duran glass powder type No. 8330, having grain sizes up to and including 100 .mu.m,
- filtering and drying the resulting mixture,
- compressing the mixture with a surface pressure of at least 1000 bar to form blanks, sintering the blanks at about 860.degree. C., and
- washing out the K.sub.2 SO.sub.4.
- 13. Open-pored sintered filter bodies composed of:
- borosilicate glass particles having grains of any size up to and including 20 .mu.m and borosilicate glass particles having grains of any size up to and including 100 .mu.m, said particles being joined by sintering to yield a mass having interstices approximating the size of salt grains which have been washed out of the interstices where said salt grains have a range of sizes of any size up to and including 40 .mu.m.
- 14. Open-pored sintered filter bodies composed of:
- borosilicate glass particles having grains of any size up to and including 20 .mu.m and borosilicate glass particles having grains of any size up to and including 40 .mu.m, said particles being joined by sintering to yield a mass having interstices approximating the size of salt grains which have been washed out of the interstices where said salt grains had a range of sizes of any size up to and including 40 .mu.m.
- 15. Open-pored sintered filter bodies comprised of:
- borosilicate glass particles having a grain size in the range of 40 to 60 .mu.m and borosilicate glass particles of any grain size up to and including 40 .mu.m, said particles being joined by sintering to yield a mass having interstices approximating the size of salt grains which have been washed out of the interstices where said salt grains have a range of sizes from 100 to 200 .mu.m.
- 16. Open-pored sintered filter bodies composed of:
- borosilicate glass particles having grains of any size up to and including 20 .mu.m and borosilicate glass particles having grains of any size up to and including 100 .mu.m, said particles being joined by sintering to form a mass, the interstices in the sintered mass having sizes approximating the size of salt grains which have been washed out of the interstices where said salt grains have a range of sizes from 100 to 200 .mu.m.
- 17. A method of producing open-pored sintered bodies comprising:
- mixing vigorously 70% by weight of K.sub.2 SO.sub.4 having grains of any size up to and including 40 .mu.m and 30% by weight of borosilicate glass powder selected from the group consisting of type No. 8330 Duran glass, No. 8230 borosilicate glass or another borosilicate glass having an alkaline concentration in the range of up to 3% by weight,
- mixing into the resulting mixture a bonding agent consisting of 100 ml of an aqueous 30% polyethylene glycol solution per kilogram of the mixture to form a parent granulate material,
- adding and mixing 10 weight percent, with respect of parent granulate material, of borosilicate glass powder with the same characteristics mentioned above,
- filtering and drying the resulting mixture,
- compressing the mixture with a surface pressure of at least 1000 bar to form blanks,
- sintering the blanks at about 920.degree. C., and
- washing out the K.sub.2 SO.sub.4.
- 18. Method for the production of open-pored sintered bodies composed of glass, having a large open-pore volume, high flexural tensile strength, predetermined pore sizes and high flow velocities for fluids and gases, by means of sintering a glass-salt mixture followed by washing out the salt, including the
- producing a first granulated material composed of a first fine grained glass powder, coarse grained salt powder, the salt having a melting point higher than the glass sintering temperature to prevent the salt from combining with the glass material, said salt being soluble in liquids that do not dissolve the glass, and a bonding material, and processing a second fine grained glass powder into a second granulated material with the aid of a bonding agent, and admixing the second granulated material with the first granulated material, subjecting the resulting mass to a molding procedure to produce a molded body and sintering the body by heating to the sintering temperature of the glass, and afterwards washing out the salt from the sintered glass.
- 19. The method according to claim 18 wherein said salt is K.sub.2 SO.sub.4.
- 20. The method according to any one of claims 18 or 19 wherein the second granulated material has grain size in the range of 63 to 400 .mu.m.
- 21. The method according to any one of claims 18 or 19 wherein the grain size of the second fine-grained glass powder includes grains of any size up to 100 .mu.m.
- 22. The method according to any one of claims 18 or 19 wherein the grain sizes of the second fine-grained glass powder includes grains of any size up to 40 .mu.m.
- 23. Open-pored sintered bodies according to any one of claims 18 or 19 having flexural tensile strengths of 7 to 12 N/mm.sup.2, pore volumes of 60% to 75% and pore diameters in the range of 10 to 15 .mu.m.
- 24. Open-pored sintered bodies according to any one of claims 18 or 19 having flexural tensile strengths of 7 to 12 N/mm.sup.2, pore volumes of 60% to 75% and pore diameters in the range of 30 to 40 .mu.m.
- 25. Open-pored sintered bodies according to any one of claims 18 or 19 having flexural tensile strengths of 7 to 12 N/mm.sup.2, pore volumes of 60% to 75% and pore diameters in the range of 80 to 100 .mu.m.
- 26. Open-pored sintered bodies according to any one of claims 18 or 19 having flexural tensile strengths of 7 to 12 N/mm.sup.2, pore volumes of 60% to 75% and pore diameters in the range of 110 to 150 .mu.m.
- 27. A method of producing an open-pored sintered body comprised of glass and being essentially free of micropores and having a pore volume of at least 60%, comprising the following steps:
- producing a parent granulated material composed of a first fine grained glass powder, coarse grained salt powder having a melting point higher than the glass sintering temperature to prevent the salt from combining with the glass, said salt being soluble in liquids that do not dissolve the glass, and a bonding material,
- adding to the parent granulated material 5 to 20 weight percent, with respect to said granulated material, of a second fine grained glass powder,
- molding the resulting mass to produce a molded body and sintering the body by heating to the sintering temperature of the glass, and
- washing out the salt from the sintered glass.
- 28. The method according to claim 27 resulting in a filter pore-size category within the range of P16 to P160 according to ISO 4793.
- 29. The body according to claim 27 wherein said first glass powder and second glass powder are the same composition.
- 30. A method of producing a sintered glass body which is essentially free of micropores and having a pore volume of at least 60%, comprising the following steps:
- producing a parent granulated material composed of a fine grained glass powder, coarse grained salt powder, having a melting temperature higher than the glass sintering temperature to prevent the salt from combining with the glass, said salt being soluble in liquids that do not dissolve the glass and a first bonding material,
- to the resulting parent granulated material admixing 5 to 20 weight percent, with respect to said parent granulated material of a second granulated material composed of a second fine grained glass powder and a bonding material,
- molding the resulting mass into a body and sintering the body by heating it to the sintering temperature of the glass, and
- washing out the salt from the sintered glass.
- 31. The method according to claim 30 wherein the sintered body has a filter pore-size category within the range of P16 to P160 according to ISO 4793.
- 32. The method according to claim 30 wherein said first glass powder and second glass powder are of the same composition.
Priority Claims (1)
Number |
Date |
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Kind |
3637690 |
Nov 1986 |
DEX |
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Parent Case Info
This is a continuation of co-pending application Ser. No. 07/116,024 filed on Nov. 3, 1987 now abandoned.
US Referenced Citations (7)
Non-Patent Literature Citations (2)
Entry |
International Standard ISO 3585, First Edition-1976-04-01 Glass Plant, Pipeline and Fittings-Properties of Borosilicate Glass 3.3. |
International Standard ISO 4793, First Edition-1970-10-01 Laboratory Sintered (Fritted) Filters-Porosity Grading, classification and designation. |
Continuations (1)
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Number |
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116024 |
Nov 1987 |
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