CERAMIC FIBER

            Inorganic fibers are attractive because of their resistance to combustion and their high thermal stability relative to organic fibers. The base material of ceramic fiber textile products consists of ceramic staple fiber yarns containing ceramic fiber and small quantity of organic fiber that decomposes from about 200°C. These yarns are reinforced either with steel wires (for 1100°C) or glass filaments (for 650°C) in order to ensure that the mechanical strength is maintained up to the high temperatures.

 

Basic Composition of Ceramic Fiber:-

SiO₂                             :           50 – 60 %

Al₂O₃                           :           30 – 50 %

Na₂O.H₂O                   :           0.1 %

Fe₂O₃                           :           0.04 %

Leachable Chlorides   :           10 ppm

 

Multifilament Ceramic Fibers (˃ 20 μm diameter)

Type	Name		Tensile Strength (Gpa)	Modulus (Gpa)	Exp. (%)	Density (g/cm3)
Silicon Carbide	Nicalon	12% O	3.0	180	1.5	2.5
	Tyranno	12% O; 11% T	2.8	210	1.5	2.4
Silicon Nitride	Tonen	4% O	2.5	300	---	2.5
Silicon Carbonitride	Fibreamic	23% N; 12% C; 4% O	1.8	220	0.9	2.4
Alumina / Silica	Nextel 312	24% SiO2; 14% B2O3	1.7	154	---	2.7
	Nextel 480	28% SiO2; 2% B2O3	2.3	224	---	3.0
	Altex	15% SiO2	2.0	230	0.8	3.2
α-Alumina	Fiber FP	[α-Al2O3]	1.4	380	0.4	3.9
	PRD – 166	15% ZrO2	1.9	380	0.6	4.2

Ceramic Fibers Properties

ð  Colour                                     :           White

ð  Fiber Diameter                        :           2 – 3 micron

ð  Specific Heat                           :           1130 J/Kg°C

ð  Fire Reaction                           :           Incombustible

ð  Resistance to Chemical agents:           Good

ð  Continuous use limit               :           1260 °C

ð  Melting Point                          :           1790 °C

ð  Excellent thermal shock resistance

ð  Good dimensional stability

ð  Low thermal conductivity

ð  Maximum temperature            :           Reinforced glass : 650 °C

                                                                  Reinforced steel wire : 1100 °C