TaC-coated Graphite EVEREDKOTE™-B

Catalog
Download Products Inquiry

EVEREDKOTE™-B is a material created by coating the surface of a highly purified graphite substrate with a fine layer of TaC (tantalum carbide) by means of a proprietary Toyo Tanso Chemical Vapor Deposition (CVD) process.
Characteristics

EVEREDKOTE™-B Surface and SEM cross-section image

Features

・Excellent heat resistance
・Prevents the separation and scattering of graphite powder, as well as the release of gases andimpurities from the graphite substrate
・Excellent resistance to reactions with etching gases

Application

・Components for single crystal SiC growth
・Components for MOCVD
・High-temperature components

Properties/Test Data

General Physical Properties

Item	Tantalum Carbide
Bulk Density	14.5Mg/m³
Melting Point	3985℃
Hardness	1550HK
Electrical Resistivity	0.15μΩ・m
Thermal Conductivity	9-22（W/m・K）
Coefficient of Thermal Expansion	7.1(10⁶/K)

* The above numerical values are those taken from the below source and are not guaranteed values.
Source: H. Holleck: Material selection for hard coatings, J. Vac. Sci. Technol. A, Vol.4, No.6, Nov/Dec 1986

Reactivity with Various Substances

Reactive Substance	1200℃×5h	1600℃×5h
Hydrogen Chloride	◎	◎
Ammonia	◎	◎
Hydrogen	◎	◎
Oxygen	× (600°C or more)

*◎:No reaction　×;Significant reaction

Hydrogen chloride reaction test: 20 Torr, HCl/H2 = 0.30/2.70 L/min (10%)
Ammonia reaction test: 20 Torr, NH3/H2 = 0.5/2.0 L/min (20%)
Hydrogen reaction test: 20 Torr, H2 3.0 L/min
Oxygen: Cracking and embrittlement of coating in low concentration oxidized atmosphere.

Reactivity with ammonium

Emissivity

Impurity analysis example mass ppm

Element	Content
B	< 0.01
N	< 5
Na	< 0.01
Mg	< 0.05
Al	< 0.01
Si	0.14
P	<0.3
S	<0.02
Cl	-0.3wt%
Ca	< 0.05
Ti	< 0.005
V	< 0.005
Cr	< 0.1
Mn	< 0.005
Fe	0.42
Co	< 0.01
Ni	0.06
Cu	<0.05
Zn	< 0.05
As	< 10
Nb	1.1
Mo	1.6

*1 < :Detection limit
*2 The figures above are measurement examples and are not to be guaranteed.