SAE J2334

Viewed from the perspective of a vehicle owner, particularly the private car owner, the period from the sixties to the eighties represented the nadir of the motor industry. The single most important factor contributing to this perception in the mind of the car owner was the very short corrosion life of vehicle components and, in particular, the bodywork. The rapid growth in motor vehicle ownership, especially in Western Europe, had led to changes in manufacturing processes, as well as material and finish specifications, which seemed to be major contributors to the much-reduced life expectancy of the vehicle compared with earlier methods.

Field experience, whilst providing a degree of information upon which motor manufacturers could base product improvements, was limited to the collation of historic data to provide a guide for the future – which does little to placate customers dissatisfied with their current vehicle's performance. What the industry yearned for was a more predictive method of testing which would allow likely component performance to be assessed before field trials and product releases. One method of testing which was shown to be particularly indicative of the performance of components in the conditions in which vehicles operate was the Cyclic Corrosion Test (CCT). Once such a testing regime could be established there remained only the challenge of correlating laboratory test results with field experience.

As a result of this early experience, the automotive industry has taken a lead role in the development of cyclic corrosion tests with the objective of producing results that better correlate with field exposure. In 1984, a joint effort, The Automotive Corrosion and Prevention Committee, which was a collaboration between the Corrosion Task Force of the American Iron and Steel Institute and the Society of Automotive Engineers, began its work. This group has worked unstintingly to develop the knowledge of corrosion mechanisms and their replication in a controlled environment until, nearly 20 years later and after considering over 130 available laboratory, proving ground, and outdoor corrosion tests, the SAE Surface Vehicle Standard, J 2334 Cosmetic Corrosion Lab Test, was published in June 1998. (1)

The development of SAE J2334 was arduous, but thorough. Ten substrate materials were selected for use in the tests to reflect the materials most commonly used and/or subject to the greatest corrosive damage in vehicle applications.. At least two substrates were chosen because the existence of proven corrosion testing results enabled them to be used to assure the consistency of the test. Canadian on-vehicle tests were conducted at Montreal, Quebec and St. John's Newfoundland for 5 years. The test panels were mounted on the vehicles in both horizontal and vertical orientations to better represent the various surface orientations typically found in vehicle applications. The corrosion mechanisms of on-vehicle and laboratory tests were studied by Lehigh University. The resulting analysis showed that similar corrosion products and modes were found in these tests as were found after conducting SAE J2334 tests. (2)

Efforts to improve the correlation and repeatability of the testing regime continue as the industry refines its efforts to provide vehicles with superior corrosion resistance and improved customer acceptance. With heightened world-wide awareness of the combined needs to better conserve raw materials, to minimise disposable hazards and to maximise recyclability the efforts of the industry can be seen as strongly supporting those aims.

And for the motorist, it means that his vehicle will remain his proudest investment for many years to come, free from the ravages of corrosion and material decay, thanks to the efforts of the industry and the guidance provided by SAE J2334.

References:

1) SAE J2334, Lab Cosmetic Corrosion Test, Society of Automotive Engineering Surface Vehicle Standard, June 1998.

2) Schafer, J, Lutze, F., "The New SAE Cyclic Corrosion Standard, J2334 - A simulation in the Laboratory of Automotive Corrosive Environments" Presented at Eurocorr 2000.