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The present paper offers a status report on round-robin tests conducted with the participation of ten laboratories, with drawbead simulation (DBS) as the test method. The results showed that, in most laboratories, the coefficient of friction (COF) derived from the test is repeatable within an acceptable range of ±0.01. Repeatability between laboratories was less satisfactory. Five laboratories reported results within the desirable band, while some laboratories found consistently higher values. In one instance this could be traced to incomplete transfer of clamp forces to the load cell, in other instances inaccurate test geometry is suspected. Therefore, numerical values of COF from different laboratories are not necessarily comparable. Irrespective of these inter-laboratory variations, the relative ranking of lubricants was not affected, and data generated within one laboratory can be used for relative evaluations and for a resolution of production problems.

A movement to adopt standard corrosion testing methods for sheet metal processing fluids is underway.1 The group formed to accomplish this mission consists of consumer and supplier representatives of both sheet steel and related processing fluids. Specifically addressed are the corrosion tests employed for qualification of coil steel ship-out protectants, pre-lubricants, and fabrication plant lubricants and rust preventatives. Although the actual requirements of sheet steel and automotive panel corrosion protection is relatively similar throughout each respective industry, a wide variety of in-house developed corrosion tests exist. These individualized tests often dictate diverse requirements for similar applications. Standardizing corrosion test methods can be seen as a first step in implementing the processing fluids compatibility concept.