Effect of alloying Cu on the corrosion resistance of stainless steels in chloride media

Effects of Cu addition on the corrosion behavior of NiCoCrMo alloys in neutral chloride solution

“…In contrast to the open-circuit potential test, 0.5Cu with higher corrosion resistance compared to 0Cu during polarization test, is possibly ascribed to the more uniform Cu distribution (increased S C ) due to the accelerated dissolutiondeposition of Cu by applied potential. 19,39 Similarly, 2Cu shows comparable corrosion resistance to 0Cu at open-circuit potential and a notable improvement on corrosion resistance from E corr onwards. 4Cu exhibits the most outstanding corrosion resistance in 3.5 mass% aerated NaCl solution, owing to its high Cu addition.…”

The Mechanism of Corrosion of Steel 304L in the Presence of Copper in Industrial Installations / Mechanizm Korozji Stali Austenitycznej 304L W Obecności Miedzi W Instalacjach Przemysłowych

“…As a result, corrosion pits with a very well developed characteristic surface form. There have been reports about the (disputable) influence of alloying austenitic steel with copper on the corrosion resistance of the former [10,11,12]. It has been found that during the corrosion of austenitic steel the ions passing into the corrosive solution can intensify the corrosion process.…”

“…An additional contributing factor is the low oxygen content due to the fact that oxygen access to the substrate of the steel is rendered difficult by the deposition of copper on its surface, which makes the restoration of the passive layer and the transition of the steel to the passive state difficult. In [12] it was found that the dissolution of austenitic steel in the presence of copper proceeds more readily when Cl ions are present in the corrosive solution. The multiplication of the processes leads to the heavy corrosion of austenite in the neighbourhood of copper precipitates (Fig.…”

Corrosion Resistance of Cu-modified 3Cr Low-alloy Steel in 3.5%NaCl Solution

“…This effect is connected with the presence of cathodic element of Cu dispersed in the ferrite matrix stimulating the anodic polarization of ferrite and enhancing the passivation process at the initial stage. 24,[29][30][31][32] However, the beneficial effect gradually weakens with increasing immersion time, because of the enough accumulation of protective corrosion products scale. Clearly, Cu demonstrates a positive effect in terms of enhancing the corrosion resistance of 3Cr steel, which is characterized by the low weight loss at the initial stage during immersion testing and a Cu-rich passive film on the steel surface.…”