Sandwich Corrosion Test of Aircraft Maintenance Materials ASTM F1110
Sandwich corrosion test is determined by the standard method ASTM F1110. This Sandwich Corrosion test method defines the procedure for evaluating the corrosivity of aircraft maintenance chemicals, when present between faying surfaces of aluminum alloys, commonly used for aircraft structures.
The standard test method for Sandwich Corrosion test by ASTM F1110 determines whether aircraft structural aluminum alloys are liable to be corroded or damaged by application of the test material during routine maintenance operations. This ASTM F1110, Sandwich Corrosion test method is used in qualification and approval for compounds employed in aircraft maintenance operation. To eliminate the necessity for elaborate weight loss measurement, the relative corrosion severity rating system is introduced which also provides numerical classification of the test result.
For ASTM F1110, Aluminum coupons having clad or anodized non clad surfaces are sandwiched together with a filter paper saturated with the test material between the coupons. The sandwiched coupons are cycled between warm ambient air and warm humid air for 7 days. The coupons are then inspected to determine whether corrosion more severe than that caused by reagent water has occurred on the surfaces exposed to the test material. This Sandwich Corrosion test method is used for solutions of dry granular material or for liquid material.
Recommended coupon size is 50 by 100 by 1.0 to 1.5 mm and the recommended filter paper size is 11 or 13 cm according to ASTM F110.
If test material is solid , then there is no need for filter paper and the area covered by test material shall also be 25 by 75 mm.
Corrosion is reported in SI units and is considered as standard. Humidity Test Cabinet, capable of maintaining 95 to 100 % relative humidity at 37.7 ± 1°C (100 ± 2°F). Oven, forced air circulation, capable of maintaining 37.7± 1°C (100 ± 2°F). Programmable temperature / humidity chamber is used.