Because of its hardness, dimensional tolerance and resistance to hydrogen, cadmium plating has been used to protect steel components in marine environments. However, Cadmium is thought to be toxic and a search is on for an alternative. In this paper, cadmium and zinc-nickel plating/coating were compared in water immersion, temperature cycling, rain, humidity, and salt fog testing.
Joint Industry Project “Materials Specification for HF Alkylation Plant” to develop test and corrosion rate measurement procedures for materials in HF environments and to develop a carbon steel materials specification w.r.t levels of residual elements and carbon in steels for HF alkylation equipment.
Analysis of a UNS N08800 hydrogen unit preheat tube that failed in service. Based on chemical and metallographic analyses the failure was attributed to liquid metal embrittlement by zinc. The zinc source is thought to be the Cu/Zn catalyst for the low temperature shift converter located downstream of the preheat tubes.
Much progress has been made in testing of offshore paint systems in the past 10 years. But more work is needed to understand what is happening and give us the confidence to correlate the laboratory accelerated test to the field service life of offshore coating systems. The new NACE Standards are a move in the right direction.
Magnesium anodes are provided to the corrosion control industry by a number of domestic and international manufacturers and distributors. Anode composition is commonly the only criterion used for quality control by the end users. Many of the anodes, however, have been shown to meet the compositional and potential specifications, and yet have had measured efficiencies as low as 7%.