# US 2016/0256807 A1 · Powder sintered metallic porous body, filter element and method for improving permeability thereof > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2016/0256807 A1 - Document ID: US20160256807A1 - Status: Published application - Kind: A1 - Application number: 14/915,177 - Filed: 2014-06-30 - Published: 2016-09-08 - Earliest claimed: 2013-08-30 - Assignees: Intermet Technologies Chengdu Co., Ltd. - Applicants: Intermet Technologies Chengdu Co., Ltd - Inventors: Lin Gao; Tao Wang; Bo Li - Web page: https://patentgrep.com/patent/US20160256807A1 ## CPC - B01D 39/2034: {sintered or bonded by inorganic agents} - B01D 39/20: of inorganic material, e.g. asbestos paper, metallic filtering material of non-woven wires (porous ceramic material {C04B38/00} ; sintering metals C22C1/04; {making porous sintered metal bodies B22F3/10, honeycomb filters B01D46/2418, materials used for filtering exhaust gases of an internal combustion engine F01N3/022, ceramic honeycomb structures C04B38/0006}) - B01D 69/12: Composite membranes; Ultra-thin membranes - B01D 71/02232: {Nickel} - B22F 3/11: Making porous workpieces or articles - C22C 19/002: {with copper as the next major constituent} - C22C 19/03: based on nickel - B01D 2325/30: Chemical resistance - B22F 2998/10: Processes characterised by the sequence of their steps - B01D: SEPARATION (separating solids from solids by wet methods B03B, B03D; by pneumatic jigs or tables B03B; by other dry methods B07; magnetic or electrostatic separation of solid materials from solid materials or fluids, separation by high-voltage electric fields B03C; centrifuges, vortex apparatus B04; presses per se for squeezing-out liquid from liquid-containing material B30B9/02; treatment of water C02F, e.g. softening by ion-exchange C02F1/42; {arrangements of air intake cleaners in gas turbine plants F02C7/05} ; arrangements or mounting of filters in air-conditioning, air-humidification or ventilation F24F13/28) - B22F: WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER (making alloys by powder metallurgy C22C); APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER - C22C: ALLOYS (treatment of alloys C21D, C22F) ## Abstract Disclosed are a powder sintered porous metal with better comprehensive properties, especially with good corrosion resistance to hydrofluoric acid, and a filter element using same. The powder sintered porous metal of the present invention has a porosity of 25-60%, an average pore diameter of 0.5-50 μm and a weight loss rate of at most 1% after being immersed into a hydrofluoric acid solution with a mass fraction of 5% at room temperature for 20 days; and the powder sintered metal porous body consists of Cu accounting for 23-40 wt %, Si accounting for 0-5% and the balance of Ni, based on the weight of the powder sintered metal porous body. The powder sintered porous metal of the present invention has good mechanical properties and machinability, and excellent corrosion resistance in acid mediums, especially in hydrofluoric acid mediums. In particular surprisingly, when Cu and Ni are introduced into the powder sintered porous metal by Cu element powders and Ni element powders doped in the raw material powders, the powder sintered porous metal has significantly improved permeability and backflushing regeneration property. ## Claims ### Claim 1 A powder sintered porous metal with a porosity of 25-60% and an average pore diameter of 0.5-50 μm is characterized in that, the powder sintered metal porous body consists of 23-40 wt % of Cu, 0-5 wt % of Si and the balance of Ni, and has a weight loss rate of at most 1% after being immersed into a hydrofluoric acid solution with a mass fraction of 5% at room temperature for 20 days. ### Claim 2 (depends on 1) The powder sintered porous metal according to claim 1 is characterized in that, the powder sintered porous metal consists of Cu and Ni elements, and the crystalline phase of the powder sintered metal porous body is a (Cu, Ni) solid solution. ### Claim 3 (depends on 1) The powder sintered porous metal according to claim 1 is characterized in that, the powder sintered porous metal contains 0.5-4 wt % of Si. ### Claim 4 (depends on 1, 2, 3) The powder sintered porous metal according to claim 1, 2 or 3 is characterized in that, the tortuosity factor of the powder sintered porous metal reaches 1.02-1.25. ### Claim 5 (depends on 4) The powder sintered porous metal according to claim 4 is characterized in that, the tortuosity factor of the powder sintered porous metal reaches at most 1.10. ### Claim 6 (depends on 1, 2, 3) The powder sintered porous metal according to claim 1, 2 or 3 is characterized in that, the average pore diameter of the powder sintered porous metal is 1-20 μm. ### Claim 7 (depends on 1, 2, 3, 4, 5, 6) A filter element is characterized in that: the filter element includes the powder sintered porous metal of anyone of claims 1 to 6. ### Claim 8 (depends on 7) The filter element according to claim 7 is characterized in that, the powder sintered porous metal is used as a support layer of the filter element, and the surface of the support layer is attached with a working layer for filtration. ### Claim 9 (depends on 8) The filter element according to claim 8 is characterized in that, the working layer is one of a nickel porous membrane and a nickel-based alloy porous membrane. ### Claim 10 A method for improving the permeability of the powder sintered porous metal, the powder sintered porous metal has a porosity of 25-60% and an average pore diameter of 0.5-50 μm, and consists of 23-40 wt % of Cu, 0-5 wt % of Si and the balance of Ni; wherein Cu and Ni are introduced into the powder sintered porous metal by Cu and Ni element powders mixed in the raw powders; the mixed powders are pressed and then sintered to prepare the powder sintered porous metal. Cu and Ni diffuse between each other during the sintering procedure, which results in a low tortuosity factor of 1.02-1.25 for the powder sintered porous metal.