Mass standards—a high-precision study of commonly used methods for cleaning stainless steel weights

摘要

Studies have been carried out of the effects of using three different cleaning methods on 1 kg stainless steel mass standards, all three methods being suitable for use in a mass calibration laboratory. The methods investigated were manual and ultrasonic cleaning using solvents, and boiling in pure water. Boiling in pure water proved the most effective and additionally produced the most stable weights with stabilities of better than 1 part in 10~(8) over a period of months. Ultrasonic cleaning was almost as effective as boiling but the weights were less stable after the cleaning process. Manual cleaning proved the least effective and the mass change produced was very dependent on the specific cleaning technique. Finally, a summary of the key features of each cleaning technique is given.