Study of the pitting corrosion for shot peening 6061-T6 aluminum alloy in sea water

الملخص EN

This paper aims to clear some influential parameters, like shape and size of shot-peening on pitting corrosion for aluminum alloy 6061-T6.

Many specimens" were "prepared for corrosion test" with dimensions of (15*15*3) mm according to ASTM G71-31 and these specimens were categorized into four group having symbols (A,B,C,D).

Three of these groups were shot peened using different ball sizes.

Group B shot by steel ball having diameter 1.25 mm while group C shot by steel ball with diameter 2.75 mm.

Steel cylinder with diameter of 2.75 mm" and length 3mm was to shot" another "specimens.

Shot "time" was fixed of (10) min.

Many tests have been carried out to measure the surface roughness, Vickers hardness ,residual stresses.

SEM micrograph for all specimens .

Corrosion test was done by cyclic electrochemical methods for all specimens in environments of "3.5% NaCl solution".

The Corrosion value has calculated by using Tafel equation.

Results obtained show that shot peening contribute in decreasing corrosion rate comparing with base metal and shot peening using steel ball give low corrosion rate than cylinder steel due to plastic deformation causes by cylinder steel and steel ball having diameter 2.75 give the best result due to residual stress .