What causes caustic embrittlement? Caustic embrittlement
results from the conjoint action of three components: • (1)
a susceptible material (carbon steel) • (2) a specific
chemical species (concentrated hydroxide) and • (3) tensile
stress (around the riveted holes)Caustic soda (NaOH) was
added in small amounts to boiler water to prevent scaling
but the presence of caustics (alkalis), usually concentrated
in crevices around rivet heads and at hot spots, combined
with the considerable fabrication stresses around rivet
holes to caused cracking of the steel boiler shells and tube
plates.
