Patents by Inventor Mats Waldenström

Mats Waldenström has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7514061
    Abstract: The present invention relates to a method of making tungsten carbide powder by dissolving at least one organic or inorganic metal salt or compound of at least one of the groups IV, V, and VI of the periodic system preferably Cr, V, Mo and W in at least one polar solvent. Powder of WO3 is added to the solution, the solvent is evaporated, the remaining powder is heat treated in reducing atmosphere, mixed with carbon and carburized.
    Type: Grant
    Filed: April 28, 2004
    Date of Patent: April 7, 2009
    Assignee: Sandvik Intellectual Property Aktiebolag
    Inventors: Rickard Sandberg, Mathias Tillman, Mats Waldenström
  • Patent number: 6673307
    Abstract: The present invention relates to a method of making a cemented carbide by mixing powder of WC and possibly other powders forming hard constituents and binder phase and pressing agent, drying, pressing and sintering whereby; the mixing is wet mixing with no change in grain size or grain size distribution of the hard constituent powders; the WC grains are coated with binder metal and deagglomerated prior to the mixing. The sintering is made by microwave sintering at 1325-1410° C. with a holding time of 5-15 min. As a result a cemented carbide with improved properties is obtained.
    Type: Grant
    Filed: March 28, 2001
    Date of Patent: January 6, 2004
    Assignee: Sandvik AB
    Inventors: Mikael Lindholm, Mats Waldenström, Mats Ahlgren
  • Patent number: 6468680
    Abstract: The present invention relates to a coated cemented carbide insert with a binder phase enriched surface zone. The WC-grains have an average grain size in the range 1.0-3.5 &mgr;m, preferably 1.3-3.0 &mgr;m and the number of WC-grains larger than 2 times the average grain size is less than 10 grains/cm2 measured on a representative polished section 0.5 cm2 large, preferably less than 5 grains/cm2, and the number larger than 3 times the average grain size is less than 5 grains/cm2, preferably less than 3 grains/cm2. The cemented carbide is made by powder metallurgical methods and is in particular characterized in that the cooling rate, CR, from the sintering temperature, ST, exhibits the relationship 10<CR·(ST-1300)/1000<17.
    Type: Grant
    Filed: February 20, 2001
    Date of Patent: October 22, 2002
    Assignee: Sandvik AB
    Inventors: Mats Waldenström, Leif &angst;kesson
  • Patent number: 6352571
    Abstract: One or more metal salts of at least one iron group metal containing organic groups are dissolved in at least one polar solvent and complex bound with at least one complex former comprising functional groups in the form of OH or NR3, (R═H or alkyl). In addition, at least one insoluble, reducible salt of at least one iron group metal is suspended in the solution. Hard constituent powder and, optionally, a soluble carbon source are added to the solution. The solvent is evaporated and the powder mass is heat treated in inert and/or reducing atmosphere. As a result, a powder mixture is obtained which, after addition of a pressing agent, can be compacted and sintered according to standard practice to form a body containing hard constituents in a binder phase.
    Type: Grant
    Filed: December 4, 1998
    Date of Patent: March 5, 2002
    Assignee: Sandvik AB
    Inventors: Mats Waldenström, Rolf Svensson
  • Patent number: 6294129
    Abstract: The present invention relates to a method of making a cemented carbide body with a bimodal grain size distribution by powder metallurgical methods including wet mixing, without milling, of WC-powders with different grain size distributions with binder metal and pressing agent, drying, pressing and sintering. The grains of the WC-powders are classified in at least two groups, a group of smaller grains and a group of larger grains. According to the method of the present invention, the grains of the group of smaller grains are precoated with a growth inhibitor with or without binder metal.
    Type: Grant
    Filed: January 13, 2000
    Date of Patent: September 25, 2001
    Assignee: Sandvik AB
    Inventor: Mats Waldenström
  • Patent number: 6273930
    Abstract: The present invention relates to a method of making a cemented carbide with submicron WC grain size with a powder metallurgical technique including milling, pressing and sintering. The method includes milling all components except WC for about three hours, then adding the WC powder and milling for about ten additional hours. In this way a cemented carbide powder with acceptable low compacting pressure is obtained.
    Type: Grant
    Filed: April 4, 2000
    Date of Patent: August 14, 2001
    Assignee: Sandvik AB
    Inventor: Mats Waldenström
  • Patent number: 6221479
    Abstract: There is disclosed a cemented carbide insert with excellent properties for machining of steels and stainless steels. The cemented carbide comprises WC and 4-25 wt-% Co. The WC-grains have an average grain size in the range 0.2-3.5 &mgr;m and a narrow grain size distribution in the range 0-4.5 &mgr;m. According to the method of the invention a cemented carbide cutting tool insert is made by mixing powders of WC, TiC, TaC and/or NbC, binder metal and pressing agent, drying preferably by spray drying, pressing to inserts and sintering. The method characterised in that a deagglomerated WC-powder with a narrow grain size distribution is used, that the powders of TiC, TaC and/or NbC are deagglomerated and that the mixing is wet mixing with no change in grain size or grain size distribution.
    Type: Grant
    Filed: April 20, 1999
    Date of Patent: April 24, 2001
    Assignee: Sandvik AB
    Inventors: Mats Waldenström, &angst;ke Östlund, Ove Alm
  • Patent number: 6214287
    Abstract: The present invention relates to a method of making a cemented carbide comprising WC, 6-12 wt. % Co and 0.1-0.7 wt. % Cr, wherein the WC-grains are coated with Cr prior to mixing and no milling takes place during the mixing step. As a result a cemented carbide with improved properties is obtained.
    Type: Grant
    Filed: April 6, 2000
    Date of Patent: April 10, 2001
    Assignee: Sandvik AB
    Inventor: Mats Waldenström
  • Patent number: 6210632
    Abstract: As there is disclosed a cemented carbide body comprising WC with an average grain size of <10 &mgr;m in a binder phase. In the cemented carbide body the WC grains can be classified in at least two groups in which a group of smaller grains has a maximum grain size amax and a group of larger grains has a minimum grain size bmin and each group contains at least 10 % of the total amount of WC grains. According to the invention bmin−amax>0.5 &mgr;m and the difference in grain size within each group is >1 &mgr;m.
    Type: Grant
    Filed: April 1, 1999
    Date of Patent: April 3, 2001
    Assignee: Sandvik AB
    Inventors: Ake Östlund, Mats Waldenström, Ove Alm