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The present study has been conducted to investigate the interaction between corrosion and erosion processes and to quantify the synergism in realistic flow environments, including sudden pipe constrictions, sudden pipe expansions, and protrusions. Tests were conducted on AISI 1018 carbon steel using 1% wt sodium chloride (NaCl) solution purged with CO 2 as the corrosive media and silica sand as the erodent.The experiments were designed to understand whether erosion enhances corrosion or corrosion enhances erosion and to evaluate the contribution of the individual processes to the net synergism. It was observed that erosion enhances corrosion and corrosion enhances erosion, with each contributing to significant synergism; however, the dominant process was the effect of corrosion on erosion.

Articles you may be interested inEffect of indium surfactant on stress relaxation by V-defect formation in GaN epilayers grown by metalorganic chemical vapor deposition GaN films on AlN buffer layers were grown on ͑111͒ silicon substrates in a vertical rotating disk metal-organic chemical-vapor deposition reactor ͑CVD, Inc.͒. The dependence of residual stress in GaN films on the V/III molar flow ratio was studied. The crystalline quality of GaN films was analyzed by x-ray diffractometry, and the x-ray lattice parameter method was used to determine the residual stress in the films by measuring the c-axis and a-axis strain separately. The x-ray results show that the residual stress decreases with an increasing V/III molar flow ratio if all other growth parameters are kept constant.

Reflective surfaces for Space Station power generation systems are required to withstand the atomic oxygen-dominated environment of near earth orbit. Thin films of platinum and rhodium, which are corrosion-resistant reflective metals, have been deposited by ion beam sputter deposition onto various substrate materials. Solar reflectances were then measured as a function of time of exposure to a rf-generated air plasma. Similarly, various protective coating materials, including MgF2, SiO2, Al2O3, and Si3N4, were deposited onto silver-coated substrates and then exposed to the plasma. Analysis of the films both before and after exposure by both electron spectroscopy for chemical analyses (ESCA) and Auger spectroscopy was also performed. The results indicate that Pt and Rh do not suffer any loss in reflectance over the duration of the tests. Also, each of the coating materials survived the plasma environment. The ESCA and Auger analyses are discussed as well.