Post by Ray Rocket on Dec 31, 2019 18:07:49 GMT
H2O2 Passivation Procedure
Recommended variance from the above procedure: test with a series of progressively higher concentration peroxide solutions, ending with HTP, rather than a single low concentration test solution (3-5 % specified in the manual).
When peroxide reacts with the surface, it will tend to produce localized heating. Because the base meta has a higher rate of thermal expansion than the oxide layer, this tends to compromise the non-reactive oxide layer. Going to a series of progressively higher concentration peroxide solutions limits the rate of thermal expansion while filling any gaps in the oxide layer that may exist.
Also, re-passivate if the component gets banged around in handling or is exposed to significant thermal cycling, as this may compromise the relatively brittle oxide layer.
Periodically inspect the supply side of the propellant filter under magnification and check pressure drop across the filter for oxide layer particulate contamination. If significant evidence of oxide particulates, inspect the tank and plumbing interiors with a boroscope and re-passivate if necessary.
Recommended variance from the above procedure: test with a series of progressively higher concentration peroxide solutions, ending with HTP, rather than a single low concentration test solution (3-5 % specified in the manual).
When peroxide reacts with the surface, it will tend to produce localized heating. Because the base meta has a higher rate of thermal expansion than the oxide layer, this tends to compromise the non-reactive oxide layer. Going to a series of progressively higher concentration peroxide solutions limits the rate of thermal expansion while filling any gaps in the oxide layer that may exist.
Also, re-passivate if the component gets banged around in handling or is exposed to significant thermal cycling, as this may compromise the relatively brittle oxide layer.
Periodically inspect the supply side of the propellant filter under magnification and check pressure drop across the filter for oxide layer particulate contamination. If significant evidence of oxide particulates, inspect the tank and plumbing interiors with a boroscope and re-passivate if necessary.
