Zinc/organic programs

This development was further accelerated when, in the late 1970s and early 1980s, chromates began to fall out of favor (for both environmental and occupational health reasons), and thus the need arose to find suitable (organic) alternatives for use as effective corrosion inhibitors. Various stabilized phosphate and zinc/organic programs were developed at this time... 

Table 8.6 Zinc [Manganese] Polymer Phosphonate [Zinc Organic] Program Selection Notes.

Due to the need to increase cycles, the limitations of zinc at high pH levels and the stripping of inhibitor film at low pH, a change is recommended to a High Stress Tolerant, All Organic Program. 

Zinc/phosphate/organic programs These are developments of the preceding programs. These types of formulations try to incorporate the best of each type of treatment but also to operate under more difficult and stressful conditions. 

Zinc/polymer/phosphonate programs Here the PO4 is completely removed and substituted with additional organics. 

The International Organization for Standardization (ISO) has implemented a worldwide atmospheric exposure program known as ISO CORRAG. This program included exposure of steel, copper, zinc, and aluminum for one, two, four, and eight years at 51 sites located in 14 nations in order to generate the necessary data to produce a classification system for predicting atmospheric corrosivity from commonly available weather data [25]. 

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