10.76 amps per square meter 1.0 amps per square foot.
**************************************************************************
Chemical composition as follows:
Impregnant
6.5 percent
maximum
Ash
1.5 percent
maximum
Moisture & Volatiles
0.5 percent
maximum
Water Soluble Matter
1.0 percent
maximum
Graphite
Remainder
Anode dimensions:
[_____] by [_____] mm inches.
]2.1.3
Mixed Metal Oxide Anodes
Mixed metal oxide anodes shall be provided by a firm that is regularly
engaged in and has a minimum 5 years experience in manufacturing and
applying mixed metal oxide coatings to titanium anode substrates. The
mixed metal oxide anodes shall be of the size indicated and shall conform
to the following requirements.
2.1.3.1
Conductive Material
Titanium substrate coated with an inert, dimensionally stable, electrically
conductive coating [with average composition of a 50/50 atomic percent]
mixture of iridium and titanium oxides with a small amount of tantalum and
ruthenium, 0.002 ohm-centimeter maximum resistivity, 50 MPa minimum
adhesion or bond strength, and capable of sustaining a current density of
100 ampere per square meter in an oxygen generating electrolyte at 66
degrees C 150 degrees F for 20 years. Sinter the mixed metal oxide coating
to the titanium surface as to remain tightly bound to the surface when bent
180 degrees onto itself.
2.1.3.2
Anode Life Test
Perform an accelerated current capacity life test on every lot of anode
wire used to construct the anode as described. The anode wire material
shall sustain current densities of 100 ampere per square meter in an oxygen
generating electrolyte for 20 years. The manufacturer shall certify that a
representative sample taken from the same lot used to construct the anode,
has been tested and meets the following criteria.
a.
The representative sample shall be 125 mm 5 inch in length and be
taken from the lot of wire that is to be used for the anode.
b.
The cell containing the anode shall be powered with a constant
current power supply for the 30 day test period.
c.
The test cell sustains a current density of 10,000 ampere per
square meter in a 15 weight percent sulfuric acid electrolyte at
66 degrees C 150 degrees F without an increase in anode to cathode
potential of more than 1 volt.
2.1.3.3
Adhesion or Bond Strength Test
Determine the adhesion or bond strength by epoxy bonding a 2.54 mm 100 mils
diameter stud to the ceramic coating and measuring the load to failure of
either the epoxy or the interface between the coating and the substrate.
SECTION 13111N
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