Abstract: A surface of an article is heated and subjected to pressure by operation of a friction stir tool. The pressure of the face of the tool on the article surface, and the speed of rotation of the tool and of its progression along the surface of the article, are controlled to progressively hot-work a specified surface area. The face of the tool may be round and have a profiled, axially extending, smaller diameter pin for higher concentration of frictional heat and load and for plasticizing a surface layer of the workpiece. Such hot work may be applied for reducing surface porosity or for producing another change in the surface microstructure, or for effecting another change in surface material properties.

Abstract: A current collector plate, also called a bipolar plate, for a fuel cell includes two facing metal sheets with fluid channels for the fuel (often hydrogen) on the non-facing side of one sheet and fluid channels for air on the non-facing side of the other sheet. Such a plate is made by applying a patterned coating of particles of a soft and reactive metal to at least one of the sheets and rolling them together so that the soft metal particles deform and interact with the facing sheets to selectively join them at the patterned areas. Pressurized fluid is introduced between the sheets to expand non-bonded portions and define the fluid channels.

Abstract: An article for texturing an electrode having a tip hardness and a tip contour is disclosed. The article includes a plate having an upper surface and a lower surface, and an indentation in at least one of the upper and the lower surface. The indentation includes a textured surface having a plurality of asperities. The textured surface has a hardness greater than the tip hardness of the electrode. The texture of the textured surface is imprinted into the tip of the electrode in response to the tip of the electrode and the textured surface being pressed against each other.

Abstract: An anti-bonding material is placed in a desired pattern onto a first sheet of conductive material. A second sheet of conductive material is roll bonded with the first sheet of material. Fluid is injected between the bonded first and second sheets of material to expand the sheets of material at the desired pattern. A flow channel is formed at the desired pattern between the first and second sheet during fluid injection.

Abstract: A method for making a current collector plate includes providing a first sheet of material having a first bonding face and a first outer face. A second sheet of material is provided having a second bonding face and a second outer face. A work area is defined on at least one of the first bonding face and the second bonding face. The first and second sheets are bonded together at a bonding area which is different from the work area. The bonded first and second sheet is placed into a die having a pattern defining at least one flow channel. Fluid is injected between the first and second sheets thereby causing at least one of the first and second sheets to project outward at the work area causing at least one flow channel to be formed in the work area as defined by the die pattern.