Patent · US Expired

Nitride coated composite silicon nitride cutting tools

US4406667A · kind A · utility

24Cited by
4References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 20, 1982
Grant dateSep 27, 1983
Priority date
Expiry dateMay 20, 2002

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/31717
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

Cutting tools and cutting tool inserts having improved mechanical and chemical wear resistance under demanding conditions of machining speed, temperature, or workpiece hardness comprise a composite silicon nitride substrate having at least one hard adherent coating layer of a refractory metal nitride. The composite silicon nitride substrate body consists essentially of particles of a refractory material uniformly distributed in a matrix consisting essentially of a first phase of silicon nitride and a refractory second phase comprising silicon nitride and an effective amount of a densification aid selected from the group consisting of yttrium oxide, hafnium oxide, the lanthanide rare earth oxides, and mixtures thereof.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.