Silicon nitride cutting tool material

Details Silicon nitride cutting tool material Silicon nitride cutting tool material

1997-06-24

1999-06-22

Group, Karl

Compositions: ceramic

Ceramic compositions

Refractory

501 972, 407119, C04B 35396

Patent

active

059142863

ABSTRACT:
There is disclosed a silicon nitride based cutting tool insert for chipforming machining of cast iron material having improved mechanical, chemical and wear properties. This is obtained by addition of one or more transition metal oxides which act as a sintering aid together with alumina and yttria and also promote the growth of elongated grains of beta silicon nitride during the sintering. Preferably, the inserts are provided with a wear resistant coating as known in the art. The ceramic cutting tool material according to the present invention comprises a beta silicon nitride matrix with total amount of 0.5-10 weight %, preferably 0.5-6 weight %, of an intergranular phase and 0.05-3 weight % of at least one secondary crystalline phase of a transition metal carbide, nitride, carbonitride and/or silicide present as spherical particles with a size of 0.1-2 .mu.m, preferably submicron (0.01-1 .mu.m). The transition metal is preferably niobium and/or tantalum. The material has less than 1 volume %, preferably less than 0.3 volume %, porosity. The beta silicon nitride grains are to at least 10%, preferably more than 20%, elongated with an aspect ratio greater than 3, preferably greater than 5. The grain diameter of the beta silicon nitride grains is in the range of 0.2-10 .mu.m, preferably 0.2-5 .mu.m, and most preferably 0.2-3 .mu.m.

REFERENCES:
patent: 4497228 (1985-02-01), Sarin et al.
patent: 5091347 (1992-02-01), Pyzik et al.
patent: 5118645 (1992-06-01), Pyzik et al.
patent: 5120328 (1992-06-01), Pyzik
patent: 5160508 (1992-11-01), Pyzik et al.
patent: 5238884 (1993-08-01), Sakai et al.
patent: 5312785 (1994-05-01), Pyzik et al.
patent: 5312788 (1994-05-01), Li et al.
patent: 5369065 (1994-11-01), Yoshimura et al.
patent: 5382273 (1995-01-01), Mehrotra et al.
patent: 5399536 (1995-03-01), Yamakawa et al.
patent: 5424256 (1995-06-01), Yoshimura et al.
patent: 5432132 (1995-07-01), Dasgupta et al.
patent: 5439856 (1995-08-01), Komatsu et al.
patent: 5618788 (1997-04-01), Higuchi et al.
patent: 5668069 (1997-09-01), Sato et al.
patent: 5744410 (1998-04-01), Komatsu et al.

Affiliated with

Also associated with

Rating

Silicon nitride cutting tool material does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Silicon nitride cutting tool material, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Silicon nitride cutting tool material will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1708035