Patents by Inventor Helen A. Brownlie

Helen A. Brownlie 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).

  • Method of sintering machinable ferrous-based materials
    Patent number: 5534220
    Abstract: A method is described for the manufacture of a sintered ferrous-based material having improved machinability, the method comprises the steps of making a mixture of a ferrous-based powder, the mixture including a compound containing at least one metal from the group comprising manganese and the alkaline-earth series of metals; at least one sulphur donating material; pressing the powder mixture and sintering the pressed mixture so as to cause the formation by reaction during sintering of at least one stable metal sulphide within the sintered material. Materials and articles made by the method are also described.
    Type: Grant
    Filed: September 30, 1994
    Date of Patent: July 9, 1996
    Assignee: Brico Engineering Limited
    Inventors: Charles G. Purnell, Mohammad S. Mahmoud, Helen A. Brownlie