Trial Number 0

Six contaminates were evaluated with only two cleaners (Micro 90 and Shopmaster) to determine the hardest to remove soils. Eighteen copper coupons were tested for each cleaner. Initial weights were recorded, and three coupons were soiled for each contaminant using a handheld swab to cover the bottom third of the substrate. The coupons were then immersed, three at a time, in a beaker with 250ml of the chosen diluted cleaner at room temperature (68F) for five minutes. Visual observations were taken during this time, and final weights were recorded after cleaning. This process was repeated for each cleaner on all six contaminants. After determining the most difficult soils to remove the procedure was repeated with additional cleaners.

Micro 90 and Shopmaster were both ineffective at removing lubricating oils from copper substrates. Shopmaster performed better than Micro 90, with percent removals of 43.70% and 27.44%, respectively. Visually coupons cleaned with Micro 90 were beginning to oxidize in some areas. According to the technical data sheet, Micro 90 is a compatible cleaner for copper alloys. However, fear of damage to coupons or parts eliminates Micro 90 as an option for an alternative cleaner.

The pictures below show two coupons cleaned with Micro 90, that were beginning to show spots of oxidation.

Micro 90 and Shopmaster were ineffective at removing lubricating oils from copper substrates when immersed in diluted solution, at room temperature, for five minutes. Future testing will include Shopmaster, but it will not include Micro 90 due to it oxidizing the coupons.