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An autodeposition process applies an organic coating to cleaned-only metal surfaces without the use of an external current. Major advantages include lower floor space requirements than other high-quality finishing methods and the absence of Volatile Organic Compounds (VOC) when using the chemicals employed in the most widely adopted process version. Of perhaps even greater importance is the energy efficiency of the process combined with its excellent throwing power. To achieve adequate film thicknesses in a 90 to 150 second immersion time, it is only necessary for the chemical coating bath to be able to wet any recessed area. An example of a commercial part suited to a low-cure autodeposition process is an automotive leaf-spring assembly which is a composite of heavy-gauge steel plates plus plastic and rubber components, the performance of which could be adversely affected by exposure to temperatures in excess of 200°F.

One measurement of the quality of a phosphated and painted metal substrate is through the use of accelerated test procedures involving corrosive environments. The subsequent test results have been found to have dependance upon the specific test procedure that was utilized. In particular, the effects of the acidulated rinse upon galvanized steel were strongly dependent upon the test procedure involving adhesion measurements after water immersion; whereas, a negligible effect was exhibited via a cyclic scab test procedure. Finally, it was determined that a chemical modification of the phosphate coating composition can alter the effects of the acidulated final rinse upon hot dipped galvanized steel with respect to adhesion performance.