Reaction Bonded Silicon Nitride (RBSN) 

Thermal reaction of silicon metal compacts
and nitrogen produces Reaction Bonded Silicon
Nitride. Complex components can be readily and
economically produced by machining the material
in the green state. RBSN is a moderately dense
form of Silicon Nitride that does not contain a
glassy second phase and therefore maintains its
mechanical properties to 1400°C. Molten metal
(nonferrous) processing applications are ideal
for RBSN because of excellent corrosion
resistance and price performance relationships. 

Reaction Bonded Silicon Nitride
(RBSN)  Properties (Typical)* 



Type 

Bulk Desity 
2.42.6 g/cm 
Porosity
(volume percent) 
2518 
Flexural
Strength (MOR)
@
RT, 4 point average 
289338 MPa
4249 ksi 
Elastic Modulus
(E)

160179 GPa
2326 Mpsi 
Poisson's Ratio
(v) 
0.230.24 
Fracture
Toughness (whiskers) 
3.03.6 
Thermal Shock
Resistance (T) 
400500°C 

*Properties vary dependent upon green
forming technique 

"PAD"
Silicon NitrideSC 

"PAD" Silicon NitrideSC is a zero porosity,
specially formulated silicon nitride material
for use in the semiconductor industry. The
material is 98% SiN with
2% densification additives. The additives are
nonalkaline metals.


"PAD" Silicon NitrideSC 
Properties (Typical) 



Bulk Desity 
3.15 g/cm 
Flexural
Strength (MOR)
@
RT, 4 point average 
100 ksi 
Elastic Modulus
(E)

46 Mpsi 
Hardness (Knoop
1 kg) 
1480 kg/mm 
Thermal
Expansion (RT1000°C) 
3.4 10/°C 
Thermal
Conductivity (RT) 
30.0 W/m*K 


"PAD" Silicon Nitride SC1 

The SC (semiconductor) grade is a fully
dense, highly pure form of silicon nitride.
Sinteririg aid content is minimized to maintain
purity and is selected for compatibility with
the extreme environments associated with Si
wafer processing. Sizes up to 500mm square or
730mm round are possible with PAD (Pressure
Assisted Densification) processmg and the
resultant products exhibit uniformly excellent
mechanical properties. 

"PAD" Silicon Nitride SC1 
Properties (Typical) 



Bulk Desity 
3.18 g/cm 
Average Grain
Size 
.50 µm 
Flexural
Strength (MOR)
@
RT, 4 point average 
640 MPa
93 ksi 
Characteristic
Strength
@
RT, 4 point 
675 MPa
98 ksi 
Weibull Modulus
(m) 
9 
Elastic Modulus
(E)

310 GPa
45 Mpsi 
Poisson's Ratio
(v) 
0.27 
Hardness (Knoop
1 kg) 
1560 kg/mm 
Fracture
Toughness (Vickers) 
5.7 MPa*m 
Thermal
Expansion (RT1000°C) 
3 3 10/°C 
Thermal
Conductivity (RT) 
30.0 W/m*K 


PSG
Silicon Nitride 

PSG Silicon Nitride is a fully dense,
pressureless sintered ceramic specifically
compounded to yield an amorphous intergranular
phase. Pressureless sintering allows for net
shape forming of complex components in a cost
effective manner. This grade is isotropic with
respect to engineering properties and offers
excellent resistance to mechanical fatigue. PSO
Si_{3}N_{4} is useful for both
large shaped, large crosssectional structures
as well as small, intricate components.


PSG Silicon Nitride  Properties
(Typical) 



Bulk Density 
3.25 g/cm 
Flexural
Strength (MOR)
@
RT, 4 point average 
689 MPa
100 ksi 
Characteristic
Strength
@
RT, 4 point 
730 MPa
106 ksi 
Weibull Modulus
(m) 
15 
Elastic Modulus
(E) 
303 GPa
44 Mpsi 
Poisson's Ratio
(v) 
0.24 
Hardness (Knoop
1 kg) 
1450 kg/mm 
Fracture
Toughness (Vickers) 
5.7 MPa*m 
Thermal
Expansion (RT1000°C) 
3.3 10 
Thermal
Conductivity (RT) 
29.5 W/m*k 
Thermal Shock
Resistance (T) 
675°C 


PSX Silicon Nitride 

PSX is a fully dense, isotropic grade of
Silicon Nitride offering excellent wear
resistance and improved elevated temperature
properties. Pressureless sintering allows for
net shape forming of complex components for a
wide variety of structural applications. Through
exact control of processing and chemistry, the
grain boundary or intergranular phase is
engineered to be crystalline in PSX Si_{3}N_{4}.
Heat engine components are an excellent
application for this material. 

PSX Silicon Nitride  Properties
(Typical) 



Bulk Density 
3.27 g/cm 
Flexural
Strength (MOR)
@
RT, 4 point average 
703 MPa
102 ksi 
Characteristic
Strength
@
RT, 4 point 
744 MPa
108 ksi 
Weibull Modulus
(m) 
14 
Characteristic
Strength
@
RT, 4 point 
641 MPa
93 ksi 
Elastic Modulus
(E) 
317 GPa
46 Mpsi 
Poisson's Ratio
(v) 
0.24 
Hardness (Knoop
1 kg) 
1480 kg/mm 
Fracture
Toughness (Vickers) 
6.0 MPa*m 
Thermal
Expansion (RT1000°C) 
3.4 10 
Thermal
Conductivity (RT) 
30.0 W/m*k 
Thermal Shock
Resistance (T) 
700°C 
