Expanded metal and process of making the same
An expanded metal is provided including a plurality of integral strands defining diamond shapes, each diamond shape having a long dimension as measured from two opposing vertices and a short dimension, generally transverse to the long direction, as measured between two other opposing vertices, such that the long dimension is less than twice the short dimension.
1. A filter comprising a filter medium reinforced with an expanded metal, wherein said reinforced filter medium and said expanded metal are pleated, said expanded metal comprising a plurality of integral strands defining diamond shapes, each diamond shape having a first dimension as measured from two opposing vertices and a second dimension, generally transverse to the first dimension, as measured between two other opposing vertices, wherein said expanded metal is formed by slitting a sheet of metal thereby preliminarily expanding said metal, wherein said slit preliminarily expanded metal having been further expanded after slitting along a direction by at least 15% per linear dimensional unit to form said expanded metal, and wherein the second dimension is along the direction of expansion.
2. The filter of claim 1 wherein the second dimension is equal to the first dimension.
3. The filter of claim 1 wherein each vertex is expanded beyond in plastic yield point.
4. The filter of claim 1 wherein the first dimension is less than twice the second dimension.
5. The filter of claim 1 wherein the second dimension is about equal to the first dimension.
6. The filter of claim 1 wherein said strands have been expanded beyond their plastic yield point.
7. The filter of claim 1 wherein the slit preliminarily expanded metal has been expanded along the direction by at least 25% per linear dimensional unit.
8. The filter of claim 1 wherein the slit preliminarily expanded metal has been expanded along the direction by at least 28% per linear dimensional unit.
9. The filter of claim 1 wherein the slit preliminarily expanded metal has been expanded along the direction by at least 30% per linear dimensional unit.
10. The filter of claim 1 wherein after slitting the slit preliminarily expanded metal first dimension is decreased by at least 15%.
11. The filter of claim 1 wherein after slitting the slit preliminarily expanded metal first dimension is decreased by at least 18.8%.
12. The filter of claim 1 wherein after being pleated said expanded metal does not spring back toward its unpleated position.