Corrosion products and corrosion-induced cracks of low-alloy steel and low-carbon steel in concrete

The distribution of corrosion products at the steel-concrete interface and the pattern of corrosion induced cracks were characterized using X-ray computed tomography (X-CT) and environmental scanning electron microscopy (ESEM). A novel low-alloy reinforcing steel (LA steel) and the conventional low carbon reinforcing steel (LC steel) embedded in concrete were subjected to impressed current accelerated corrosion. The results of Raman spectroscopy showed that non-protective lepidocrocite (gamma-FeOOH) was the main corrosion products for LC steel, while stable and protective maghemite (gamma-Fe2O3) and less crystallized feroxyhite (delta-FeOOH) and ferrihydrite (5Fe(2)O(3)center dot 9H(2)O) were identified in the Cr-enriched inner rust layer of LA steel. (C) 2018 Elsevier Ltd. All rights reserved.