Materials based on porous cubic crystal series boron nitride for post production of cutting tools and preparation method thereof

Application Number: 00105718
Application Date: 2000.04.03
Publication Number: 1269273
Publication Date: 2000.10.11
Priority Information: 1999/4/7 SE 9901222-1
International: B22F3/11;B22F7/06;C22C29/14
Applicant(s) Name: Sandvik AB
Inventor(s) Name: Ulf Roland;Jeorord Vein
Patent Agency Code: 72002
Patent Agent: gan ling
Abstract The presently claimed invention relates to a method of making a PcBN cutting tool insert. The method includes the following steps: mixing raw material powders, (e.g., cBN, hBN, TiC, TiN, Ti(C,N), WC, W, C, Co, Co2Al9, Al AlN, Al2O3) with a liquid (e.g., ethanol) and an agent (e.g., polyethylene glycol, PEG) to form a homogeneous slurry with the desired composition; forming spherical powder agglomerates, typically 100 mum in diameter, preferably by spray drying; pressing said agglomerates to form a body of desired dimensions and density using conventional tool pressing technology; removing the agent from the powder at a suitable temperature and atmosphere; raising the temperature to 1000-1350 DEG C in vacuum; solid state sintering the body at 1000-1350 DEG C in vacuum, for 1-90 minutes to form a body with 35-55 vol % porosity; optionally, adding 0.5-1000 mbar of nitrogen to the sintering atmosphere at the hold time or during cooling; and HP/HT treating the porous body to form a dense body of desired shape and dimension.