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3700 |
Cross section of boiler steel corroded in 0.5 n NaOH at 310_C for 2
days in order to produce a protective magnetite coat. (foto KEMA, ref 6). |
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3700 |
Pre-oxidised steel sample at the end of a long term experiment in 0.1 n NaOH at 310_C with the addition of 0.5 g CuO.
Pos a: Cross section at the copper coated position a.
Pos b: Cross section at the grey position b. above the copper coated zone a.
Pos c: Cross section at the red upper part c. (foto KEMA, ref 6). |
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3701 |
Fig A; The electron transport with iron corrosion under the influence of copper oxide reduction.
Fig B; Schematic representation of the influence of resistance polarization on the iron rest potential. (foto KEMA, ref 6). |
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3702 |
Cross section of a magnetite layer which has been destroyed by reduction of CuO after a
long term experiment in 1.10-5 n NaOH . Fine grained -Fe203 and copper can be recognized. (foto KEMA, ref 6). |
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3703 |
Left: The oxide layer after a long term experiment in 0.1 n NaOH without copper addition.
Right: The oxide layer after a long term experiment in 0.1 n NaOH with copper addition. Platelets of alpha-Fe2O3 have grown between the copper particles. (foto KEMA, ref 6). |
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3704 |
The oxide layer on an evaporator tube of a 170 kg/cm2 absolute pressure boiler after 10500 operating hours. Upper: A: unheated side, B: heated side
Below: The oxide layer on a decarburated evaporator tube C: unheated side, D: heated side. (foto KEMA, ref 6). |
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3705 |
A: Pitting and copper in the pits of a steam receiver in a 73 kg=cm2 absolute pressure boiler (fig 20) B: Cross-section of an oxide coat on an evaporative tube of a 165 kg=cm2 absolute boiler. Under the amorphous copper-rich oxide a protective magnetite coat has grown.
C and D: Homogenous unbroken oxide layers growing on an evaporator tube of a 150 kg=cm2
absolute boiler after 58000 operating hours. C: unheated position, D: heated position. E: Oxide layer on an evaporative tube of a 130 kg=cm2 absolute boiler. (foto KEMA, ref 6). |
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3706 |
Polarisation curves, measured with iron in 1.10-4 n NaOH and 1. 10-2 n NaOH at 250°C. (ref 6). |
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3707 |
Polarisation curve for copper 0.001 n NaOH at 250 0 C. (ref 6). |
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3708 |
Polarisation curve for copper 0.01 n NaOH at 250 0 C. (ref 6). |
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