← Back to Patent Explorer
US4881950A Expired / Lapsed US ⏱️ 0.0 years remaining

Silicon nitride cutting tool

Assignee: Valenite LLC
•
Filing: 1987-10-05
•
Granted: 1989-11-21
•
Expires: 2007-10-05
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A coated densified ceramic cutting tool has a granular phase of silicon nitride, silicon aluminum oxynitride, and a reaction formed submicron refractory metal nitride uniformly distributed in a matrix of a suitable densification aid with a coating comprising an interfacial layer of titanium nitride followed by at least one layer of refractory metal material.

Inventors

  • 👤 Deepak Bhat
  • 👤 Dhirajlal Shah

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-06 16:03
CPC Classifications
C; C04; C04B; C04B41/00; C04B41/009; B; B24; B24D; B24D3/00; B24D3/007; B24D3/02; B24D3/04; B24D3/14; B24D3/18; C04B35/00; C04B35/515; C04B35/58; C04B35/584; C04B35/593; C04B35/5935; C04B35/597; C04B35/622; C04B35/626; C04B35/62605; C04B35/6261; C04B35/62645; C04B35/62655; C04B35/63; C04B35/632; C04B35/64; C04B35/645; C04B35/6455; C04B41/45; C04B41/52; C04B41/80; C04B41/81; C04B41/89; C04B2235/00; C04B2235/02; C04B2235/30; C04B2235/32; C04B2235/3205; C04B2235/3206; C04B2235/3217; C04B2235/3224; C04B2235/3225; C04B2235/3231; C04B2235/3232; C04B2235/34; C04B2235/3418; C04B2235/38; C04B2235/3852; C04B2235/3865; C04B2235/3873; C04B2235/3878; C04B2235/3886; C04B2235/65; C04B2235/656; C04B2235/6567; C04B2235/70; C04B2235/74; C04B2235/76; C04B2235/766; C04B2235/77; C04B2235/80

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 147 words
A coated densified ceramic cutting tool comprising, a substrate body consisting essentially of a granular phase of alpha silicon nitride and silicon aluminum oxynitride, said granular phase being uniformly distributed in a matrix of a densification aid, selected from the group consisting of magnesium oxide, yttrium oxide, rare earth oxides, and mixture thereof, said matrix including uniformly distributed submicron particles consisting essentially of titanium nitride, said silicon aluminum oxynitride and said titanium nitride being formed during densification of said tool by reaction of titanium oxide with a portion of said silicon nitride to form titanium nitride and silicon oxide, a layer of refractory material, and an interfacial layer intermediate said substrate and said layer of refractory material, said interfacial layer comprising a titanium metal chemically reacted to form a reaction bonded titanium nitride for enhancing the adherence of said layer of refractory metal material to said substrate.
Claim 2
Dependent Claim 147 words
A coated densified ceramic cutting tool comprising, a substrate body consisting essentially of a granular phase of alpha silicon nitride and silicon aluminum oxynitride, said granular phase being uniformly distributed in a matrix of a densification aid, selected from the group consisting of magnesium oxide, yttrium oxide, rare earth oxides, and mixture thereof, said matrix including uniformly distributed submicron particles consisting essentially of titanium nitride, said silicon aluminum oxynitride and said titanium nitride being formed during densification of said tool by reaction of titanium oxide with a portion of said silicon nitride to form titanium nitride and silicon oxide, a layer of refractory material, and an interfacial layer intermediate said substrate and said layer of refractory material, said interfacial layer comprising a titanium metal chemically reacted to form a reaction bonded titanium nitride for enhancing the adherence of said layer of refractory metal material to said substrate.
Claim 3
Dependent Claim 39 words
A coated densified ceramic cutting tool according to claim 1 wherein said silicon aluminum oxynitride has the formula: Si 6-x Al x O x N 8-x where x is greater than zero and less than or equal to 4.2.
Claim 4
Dependent Claim 18 words
A densified ceramic cutting tool according to claim 2 wherein x is from about 0.1 to about 2.0.
Claim 5
Dependent Claim 42 words
A coated densified cutting tool according to claim 1 wherein said layer of refractory material comprises at least one layer selected from the group consisting of refractory metal oxides, refractory metal carbides, refractory metal nitrides, or refractory metal carbonitrides and combinations thereof.
Claim 6
Dependent Claim 18 words
A coated densified cutting tool according to claim 4 wherein said layer of refractory material comprises titanium carbide.
Claim 7
Dependent Claim 39 words
A coated densified cutting tool according to claim 4 wherein said layer of refractory material comprises a layer of titanium carbide adjacent to said interfacial layer and a layer of aluminum oxide adjacent to said layer of titanium carbide.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1992-11-20 1993-05-22 1993-11-21 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1996-11-20 1997-05-22 1997-11-21 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2000-11-20 2001-05-22 2001-11-21 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag