Sintering method, particularly for forming low ESR capacitor anodes
View Patent ↗A method of making a sintered article in which a solid object is embedded includes forming a green body of compressed particles with the solid body is partially embedded. The green body includes an opening across which the solid body extends. The green body is sintered to form a sintered body and the opening permits deformation of the solid body in response to stress applied during the sintering process. A sintered article in which a solid body is at least partially embedded includes an opening. The solid body extends across the opening so that the solid body can deform within the opening. The opening in the solid body prevents distortion of the sintered body from a planar configuration during sintering, even when the green body is relatively thin.
1. A method of making a sintered valve metal anode precursor for a capacitor, the method comprising:
compressing particles of a valve metal together to form a green body having an area, a thickness that is measured transverse to the area, an opening extending into the thickness of the green body, and a solid body at least partially within the green body and extending across the opening in the green body; and
sintering the green body so that the particles of the valve metal form a sintered body and stress applied to the solid body in the sintering is relieved by deformation of the solid body in the opening.
2. The method of making a sintered valve metal anode precursor according to claim 1 including, before sintering the green body, forming an arcuate portion of the solid body within the opening.
3. The method of making a sintered valve metal anode precursor according to claim 1 including, before sintering the green body, severing the solid body within the opening.
4. The method of making a sintered valve metal anode precursor according to claim 1 , wherein the area includes at least one linear dimension, the linear dimension divided by the thickness of the sintered body is at least 5, and the sintered body is substantially planar.
5. The method of making a sintered valve metal anode precursor according to claim 1 , wherein the solid body extends from substantially a first edge of the green body, through the opening, and substantially to a second edge of the green body.
6. The method of making a sintered valve metal anode precursor according to claim 1 including, after forming the sintered body, anodically oxidizing the valve metal particles of the sintered body.
7. The method of making a sintered valve metal anode precursor according to claim 1 including forming the opening to pass entirely through the green body.
8. A method of making a sintered article comprising:
compressing particles of a material together to form a green body having an area, a thickness that is measured transverse to the area, an opening extending into the thickness of the green body, and a solid body at least partially within the green body and extending across the opening in the green body; and
sintering the green body so that the particles of the material form a sintered body and stress applied to the solid body in the sintering is relieved by deformation of the solid body in the opening.
9. The method of making a sintered article according to claim 8 including, before sintering the green body, forming an arcuate portion of the solid body within the opening.
10. The method of making a sintered article according to claim 8 including, before sintering the green body, severing the solid body within the opening.
11. The method of making a sintered article according to claim 8 , wherein the solid body extends from substantially a first edge of the green body through the opening, and substantially to a second edge of the green body.