The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 23, 2002
Filed:
Feb. 14, 2001
Siegfried Schiller, Dresden, DE;
Klaus Goedicke, Dresden, DE;
Fred Fietzke, Dresden, DE;
Olaf Zywitzki, Freiberg, DE;
Mats Sjöstrand, Kista, SE;
Björn Ljungberg, Enskede, ES;
Tomas Hilding, Mariefred, SE;
Viveka Alfredsson, Lund, SE;
Other;
Abstract
The present invention describes a coated substrate material. The coating is formed by one or more layers of refractory compounds of which at least one layer of fine-grained, crystalline &ggr;-phase alumina, Al O , with a grainsize less than 0.1 &mgr;m. The Al O layer is deposited with a bipolar pulsed DMS technique (Dual Magnetron Sputtering) at substrate temperatures in the range 450° C. to 700° C., preferably 550° C. to 650° C., depending on the particular substrate material. Identification of the &ggr;-phase alumina is made by X-ray diffraction. Reflexes from the ( ) and ( ) planes occurring at the 2&thgr;-angles 45.8 and 66.8 degrees when using Cu radiation identify the &ggr;-phase Al O . The alumina layer is also very strongly textured in the [440]-direction. The Al O layer is virtually free of cracks and halogen impurities. Furthermore, the Al O layer gives the cutting edge of the tool an extremely smooth surface finish.