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The purpose of this paper is to communicate and share experiences with stakeholders on how the sustainability threats and challenges associated with managing Lake Kariba and the Kariba Dam wall are being managed by the Zambezi River Authority (ZRA).

The case study area is Lake Kariba and Kariba Dam wall located in the mid‐Zambezi river basin. The data and information for the case study is from ZRAs own records.

The case study concludes that the threats and challenges so far experienced have been mitigated adequately with management programmes and tools having been put in place. However, a lot still needs to be done to improve the socio‐economic living conditions of the displaced Tonga/Korekore people.

Lake Kariba was created in the late 1950s to provide water primarily for hydro‐power production. However, this water resource now serves many users and has its sustainability threats; invasive weeds, water pollution, cyclic drought and flood events, the competing uses and multiple legislative provisions. The Kariba Dam wall, as an engineering structure, has its own sustainability challenges; effects of alkaline aggregate reaction, the spillway plunge pool stability and the general ageing of the dam structure. The Tonga/Korekore people, who were displaced on both banks of the Zambezi River when Kariba Dam was built, still feel short‐changed. Stakeholders will be able to associate and relate to similar threats, challenges and experiences and use the management solutions being applied at Kariba. The opinions and conclusions drawn in this case study are those of the author.

In this study, corrosion behavior of X53CrMnNiN219 austenitic stainless steel (SS) and X45CrSi93 martensitic SS, as well as the galvanic corrosion produced by coupling of these dissimilar alloys, are evaluated in a 3.5 Wt.% NaCl solution at temperature 25°C ± 1°C.

The corrosion parameters were estimated through a series of electrochemical tests, including Tafel polarization, electrochemical impedance spectroscopy (EIS), and zero-resistance ammeter (ZRA) technique.

The results of polarization measurements indicate that the value of corrosion current in the galvanic pair is slightly higher than that of both the austenitic and martensitic SS during the initial time of immersion in the chloride solution, which is an indication of compatibility of members in the couple. The galvanic current density measured by ZRA technique shows negative values throughout the test; accordingly, the martensitic SS acts as anode of the pair and corrodes preferentially. Localization index values are limited to the mixed corrosion process, showing relative susceptibility of the martensitic alloy to the uniform and localized corrosion (pitting) due to chloride ions.

The originality is the evaluation of galvanic corrosion susceptibility of X53CrMnNiN219 and X45CrSi93 SSs in chloride solution by the various electrochemical methods consisting of Tafel polarization, EIS, and (ZRA) technique. To our knowledge, no work has been reported on this issue for these chemical compositions under this condition up to now.

In this study the aim was to investigate under-deposit corrosion (UDC) behavior and the action effects of amino trimethylene phosphonic acid (ATMP) in the oxygen-contained solution.

Electrochemical methods and wire beam electrode techniques were used for the study of ATMP action effect for X65 steel under silica sand and CaCO₃ particle deposit. Electronic coupon technique was used for the study of galvanic effect caused by the deposits and the action effect of ATMP.

ATMP would cause localized corrosion for the silica sand-covered steel. However, it could inhibit the localized corrosion of the steel beneath CaCO₃ particle deposit. Galvanic effect test showed that the galvanic effect caused by the deposits was an important factor for the acceleration of UDC. ATMP had an obvious promotion effect for the galvanic current between bare coupon and silica sand covered coupon and different degrees of localized corrosion were observed beneath both deposits.

The authors believe that the paper may be of particular interest to the readers of the journal as the measurement methods for the UDC of X65 pipeline steel. The experiment they did in the laboratory found that the inhibitor ATMP has a good inhibition effect for bare steel, but it would accelerate the UDC. Different kinds of deposits would have different influences for the UDC behavior with inhibitor added.

The purpose of this paper is to study the patterns of formation of anti-corrosion properties, the development of compositions for pigments by using the method of co-precipitation and subsequent heat treatment.

To obtain co-precipitated hydroxides, aqueous solutions of salts were used. The conditions of synthesis varied according to the following parameters: the nature of the starting salts of metals; and the ratio of metal cations. The anticorrosive activity of the pigments was evaluated by the potentiodynamic method, by comparing the anodic and cathodic polarization curves, and calculated potentials and corrosion currents on the basis of regions of Tafel on curves. Polarization curves were obtained by using Potentiostat/Galvanostat/ZRA Gamry, which connected to the PC, and by using the program Gamry Framework. The measurement results were processed by using the method of simplex-lattice planning. X-ray diffractograms of pigments were recorded on a DRON – 2.0 diffractometer (monochromatic copper radiation with a nickel filter).

The paper deals with the results of research the dependence of colour characteristics and anticorrosion properties of synthesized compositions on their nature and composition. The presence of aluminium cations leads to the formation of solid solutions of ferrum and aluminium oxyhydroxides.

The main technological properties of pigments are determined by the anionic and cationic composition. Colour characteristics are determined by the cation-chromophore. The anti-corrosive properties of non-calcined pigments are determined to a greater extent by the presence of the formed hydroxyl ions and the composition of the compounds. The greatest protective effect is observed when using double compounds of metals, the dissociation constants of which differ significantly. The protective effect is mainly determined by the slowdown of the anode process. Anions containing aluminium atoms accelerate the corrosion processes.

To study the early stages of damage by corrosion fatigue (CF) in an austenitic stainless steel using the electrochemical noise (EN) Technique.

Potential and current transients measured between two nominally identical electrodes during CF of an UNS S31603 SS were continuously monitored using a zero‐resistance‐ammeter at different periods of exposure to seawater. The tests were carried out under cyclic loading of constant amplitude, stress ratio R=0 and load frequency of ω=0.17 Hz. The analysis was focused on both, crack nucleation sites and short fatigue crack growth, and the correlation between corrosion‐fatigue cracking and characteristics of potential transients and the associated intensity current.

Measurements of EN, showed a good relationship between the potential transients and current fluctuations with the initiation and growth of inter‐granular corrosion‐fatigue cracks. The amplitude and frequency of potential transients and the intensity of current transients became more intense as the number of loading cycles increased. The initiation of crack events and small crack growth could be associated with the noise patterns with amplitudes of 20 and 70 mV and current density between 0.10 and 0.60 μA cm²; while large inter‐granular crack growth events, were due to coalescence of small cracks, and could be associated with patterns of 200 mV in amplitude and a cathodic current density of 8.0 μA cm². The crack nucleation sites generally were located at grain boundary triple points on the specimen surface.

The EN Technique can be a good alternative to evaluate the early stages of damage by CF.

This work investigates the single substrate (SS) technique for obtaining potential and current noise data for electrochemical noise measurement (ENM) analysis. The technique uses a single substrate element, and has shown promise as a useful application for use in the field. The traditional two working electrode approach of obtaining data is hindered by the fact that two electrically isolated substrate elements are required to act as working electrodes. The SS technique addresses this problem, theoretically enabling ENM to be made on any structure using just one electrical connection to the metallic substrate. Results are presented for anti‐corrosive organic coating systems intended for marine applications that have very high resistance values (> 1 × 10⁹ohm‐cm²). In addition data obtained from previous work that looked at a single coat anti‐corrosive primer after a short period of time in immersion and giving R_n values of around 1 × 10⁸ohm‐cm² are presented. Good agreement is seen between values of R_n obtained from the traditional two working electrode method and those obtained from the single substrate technique over both ranges of resistance.

The purpose of this paper is to critically explore the interactions of key stakeholders and their impact upon corporate social responsibility (CSR) practices in the Zambian copper mining sector. In particular, the authors examine the power dynamics that emerge in the stakeholder interactions.

The authors analyse the stakeholder interactions based on the varying degrees of stakeholder salience and critical collaboration potential, and draw on rich evidence from 43 interviews with multiple stakeholders involved in CSR in the Zambia mining sector.

This paper finds stark power asymmetries in the relationship between the state, the civil society and mining companies which are exacerbated by a number of factors, including divisions within these key stakeholders themselves. Apart from power imbalances within and between stakeholders, the potential for critical collaboration at the local level is further challenged by the lack of commonly accepted social and environmental frameworks, transparency and accountability of the leadership of stakeholder groups. However, despite these power asymmetries some limited agency is possible, as civil society in particular co-opts previously dormant stakeholders to increase its own salience and, more importantly, that of the state.

This paper contributes to the literature on the key stakeholders’ interactions shaping CSR in developing countries by exploring these issues in a critical industry, the Zambian copper mining sector, on which the state economy is so heavily dependent.