TY - JOUR ID - TI - The Susceptibility of 7020 Al-alloys to Pitting Corrosion at Various Heating Temperatures AU - Karim M. Ali AU - Entsar N.Farhan AU - Sami I. J. Al-Rubaiey PY - 2010 VL - 14 IS - 61 SP - 33 EP - 46 JO - journal of the college of basic education مجلة كلية التربية الاساسية SN - 18157467 27068536 AB - The present work is aimed to investigate the effect of heat treatments variables ( temperature & time holding) on the tendency of high strength Al-alloys type 7020.
The experiments were carried out by heating the specimens at different temperatures (100, 150, 200, 250, 300, 350, 400, 450 and 500 °C) for two periods of holding time, one and two hours.
Polarization technique was used to study the effects of microstructures on their electrochemical behavior in 3.5 % NaCl solution.
Microscopic & X- ray examination had been used to reveal pitting corrosion on the microstructure of non heated and heated 7020 Al-alloys .
The results refer to as temperatures of heat treatment increase from 100-500°C pitting corrosion appears on the precipitated phases.Pitting corrosion tendency increase with increasing temperature of heating. Increase time holding of heat treatment from 1 hr. to 2 hrs would increase the pitting corrosion.

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