Home | Company Profile | Chromium | Cobalt | Hydrogen Storage Alloy | Ceramics | Ferrite | Contact | JMC Japan

JMC (USA), Inc.

Silicon Nitride Ceramics

Ceramics Home | Grades and Specs | Thermocouple Protection | Heater Protection | Metal Degassing | Flame Diffuser

Grades and Specifications

JMC's Ceramics Product Line Includes:

Thermocouple Protection Tubes
Heater Protection Tubes
Metal Degassing Equipment
Burner Flame Diffusers
Vega's Robe (release agent)
Miscellaneous shapes including hooks, nozzles and ladles

Silicon nitride ceramics exhibit superior corrosion resistance
for molten metals including aluminum, zinc and brass.

Grade Description Characteristics
NSSN Pressureless sintered Well balanced and versatile material -- our standard.
BNSN Boron nitride composite High resistance to thermal shock and elevated temperature, excellent machineability.
WRSN Whisker reinforced Superior thermal shock resistance and mechanical strength.
RBSN Reaction bonded Minimal deterioration at elevated temperatures, an economical alternative.

Material Properties

Grade NSSN BNSN WRSN RBSN
Structure Dense Dense-Porous Dense Porous
Composition (%) - BN 5, 10, 20% SiC(w)
20%
BN 10, 20%
or SiC 50%
Bulk density
(g/cm3)
3.1 2.1-2.5 3.2 2.1-2.3
Apparent porosity
(%)
<0.1 7-24 <0.1 24-28
Flexural strength
(MPa)
690 160-620 940 40-100
Thermal shock resistance
( oC)
700 >1000-850 >1000 700-450
Fracture toughness
(MPa.m1/2)
4.8 - 7.5 -
Thermal conductivity
(W/m.k)
18.4 - 29.6 4-12
Applications Thermocouple protection
& Heater
protection tubes,
precision mechanical
parts
Nozzles, Stoppers
etc.
Boiler parts
(burner
diffuser,
air nozzle), plasma related parts
Nozzles,Stoppers
etc.

Ceramics Home | Grades and Specs | Thermocouple Protection | Heater Protection | Metal Degassing | Flame Diffuser


Home | Company Profile | Chromium | Cobalt | Hydrogen Storage Alloy | Ceramics | Ferrite | Contact | JMC Japan