Dense silicon nitride body having high strength, high Weibull modulus and high fracture toughness

Number of patents in Portfolio can not be more than 2000

United States of America Patent

PATENT NO 8652981
APP PUB NO 20120190530A1
SERIAL NO

12657455

Stats

ATTORNEY / AGENT: (SPONSORED)

Importance

Loading Importance Indicators... loading....

Abstract

See full text

Silicon nitride materials with high strength, fracture toughness values, and Weibull moduli simultaneously, due to unique large grain reinforcing microstructures and well engineered grain boundary compositions. The invention demonstrates that, surprisingly and contrary to prior art, a silicon nitride material can be made which simultaneously has high strength above about 850-900 MPa, a Weibull above about 15 and high fracture toughness (above about 8 and 9 MPa·m1/2), and has reinforcing grains longer than 5 μm, typically longer than 10 μm in the microstructure without compromising its properties and reliability. The product of this invention can be processed using a variety of densification methods, including gas-pressure sintering, hot pressing, hot isostatic pressing, but is not limited to these, and does not require multiple heat treatments for all of these features to be achieved.

Loading the Abstract Image... loading....

First Claim

See full text

Family

Loading Family data... loading....

Patent Owner(s)

Patent OwnerAddress
CERADYNE INC3169 RED HILL COSTA MESA CA 92626

International Classification(s)

  • [Classification Symbol]
  • [Patents Count]

Inventor(s)

Inventor Name Address # of filed Patents Total Citations
Mikijelj, Biljana Cerritos, US 12 206

Cited Art Landscape

Load Citation

Patent Citation Ranking

Forward Cite Landscape

Load Citation

Maintenance Fees

Fee Large entity fee small entity fee micro entity fee due date
11.5 Year Payment $7400.00 $3700.00 $1850.00 Aug 18, 2025
Fee Large entity fee small entity fee micro entity fee
Surcharge - 11.5 year - Late payment within 6 months $160.00 $80.00 $40.00
Surcharge after expiration - Late payment is unavoidable $700.00 $350.00 $175.00
Surcharge after expiration - Late payment is unintentional $1,640.00 $820.00 $410.00