The Influence of Corrosive and Aggressive Environments on the Contact of Aluminum and Titanium Alloys With CFRP Under Vibration Loading Conditions

A study of the influence of the corrosive environment of seawater and an aggressive alkaline environment on the contact of the aluminum alloy D16T and the titanium alloy Ti6Al4V in a pair with the composite material CFRP under the action of the vibration factor is presented. Catastrophic destruction of the Al-CFRP contact in the conditions of the alkaline environment KOH with pH 11 was established. It was determined that the alloy D16T is very sensitive to changes in the environment. When tested in a NaCl solution, its wear increased by 1.4 times. The wear of the titanium sample decreased due to the presence of water and a humid environment in the friction zone, which lubricated the friction surfaces in some places. Temperatures of 20 ºС did not allow the processes of hydrogenation of the titanium alloy surface to occur, and as a result of the test, we record a decrease in wear by 1.09 times compared to the study in air. It has been established that the wear of the D16T material in salt water is a complex phenomenon that combines chemical corrosion and mechanical abrasion, which is often called three-component or combined corrosion. Mechanical loads caused by vibration additionally accelerate the destruction process, since the worn surface becomes even more susceptible to the aggressive effects of salts. Titanium alloys are much more resistant to the marine environment. It has been determined that high pH values actively affect the D16T and Ti6Al4V materials, sometimes leading to the destruction of passivating oxide films that naturally form on the materials. Catastrophic destruction of the D16T alloy shows chemical degradation and dissolution in an alkaline environment, which increases the wear of the material by more than 4 times.