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 | On Corrosion of Ferrous Metals in Typical Indian Soils Part I : Cast Iron
Author : Vats, Shanti Sarup ;Tripathi, Brajendra Nath
Source : Defence Science Journal ; Vol:15(1) ; 1965 ; pp 13-25
Subject : 621.78.019.84 Corrosion;546.3 Metals;546 Inorganic Chemistry
Keywords : Ferric Oxide ;Statistic;Schwerdtfeger's Soil Corrosion;Indian Soils;Iron
Abstract : Corrodibility of cast iron in ten typical Indian soils, employing Schwerdtfeger's soil corrosion cell procedure and the physico-chemical properties of the soils responsible for their corrosivity have been determined. The results have been statistically analysed, interpreted and correlated with various factors. Corrosion of cast iron in non acidic soils (p/supH4-10) proceeds through electro-chemical mechanism. Usually the rate of corrosion is maximum at the beginning and with development of the film of corrosion products, the rate gradually decrease with time until it becomes more or less constant, 'Even' general corrosion is observed on most of the cases. The maximum penetration is directly proportional corrodibility. The corrosivity of soils in situ is directly poroportional to the moisture equivalent or, in turn, to the clay content. The corrosivity of soils increases with the concentration at soluble electrolytes. Ferric oxide present in a laterite soil functions as a cathodic depolariser and hence increases its corrosivity. In an acidic soil, the corrosion mainly proceeds through the mechanism of direct chemical reaction. |
| | Corrosive Influence of Natural Geoelectric Currents
Author : Tripathi, Brajendra Nath
Source : Defence Science Journal ; Vol:16(2) ; 1966 ; pp 65-74
Subject : 550.3 Geophysics
Keywords : Earth's core;Physico chemical nature;Magnetic storm's
Abstract : A brief descriptions of natural geoelectric currents emancipating from earth's core, induced by ionospheric currents, magnetic crochets, magnetic storms, tidal movements and local earth currents due to spontaneous polarisation, junction potential, membrane potential, streaming potential, differential temperature cell action and lightning discharge have been given and the order of the currents due to these causes has been evaluated. The order indicates that the local earth currents due to physico-chemical causes in the earth may significantly add to the corrodibility of metals due to the physico-chemical nature of the soil. Longline telegraph cables may sometimes be damaged by corrosion due to the current induced by magnetic storms. The effect of all other geoelectric currents on the corrodibility of metals in soil is insignificant. |
| | On Corrosion of Ferrous in Typical Indian Soils-Part II Wrought Iron
Author : Vats, Shanti Sarup ;Tripathi, Brajendra Nath
Source : Defence Science Journal ; Vol:15(3) ; 1965 ; pp 177-184
Subject : 621.78.019.84 Corrosion;631.4 Soil Science
Keywords : Wrought ;Acidic;Penetration;Pitting
Abstract : Corrosion of wrought iron in ten Indian soils, employing Schwerdtfeger's soil corrosion cell procedure has been studied. The corrosion of wrought iron n non-acidic solid proceeds through electrochemical mechanism. Usually the rate of corrosion is maximum at the beginning and with the development of the film of the common products, the rate gradually decreases with time until it becomes more or less constant . In most of the cases 'uneven' general or local corrosion with pittings is observed. The maximum penetration is directly proportional to the corrodibility. Soils having moisture equivalent in the range 25-30% are most corrosive. The corrosivity of soils increases with increase in the concentration of soluble electrolytes. Ferric oxide present in laterite soil functions as a cathodic depolariser and hence increase the corrosivity. In and acidic sol the corrosion mainly proceeds through the mechanism of direct chemical reaction . The results have also been analyzed and correlated with various factors. |
| | On Corrrosion of Ferrous Metals in Typical Indian Soils Part II-Mild Steel
Author : Vats, Shanti Sarup ;Tripathi, Brajendra Nath
Source : Defence Science Journal ; Vol:15(2) ; 1965 ; pp 131-138
Subject : 631.4 Soil Science;621.78.019.84 Corrosion
Keywords : Non-acidic soils ;Indian Soil;Corrosion of Metals
Abstract : Corrosion of mild steel in ten Indian soils, employing Schwerdtfeger's soil corrosion cell procedure, has been studied. The results have been analysed and correlated with various factors. The study reveals that the rate of corrosion in non- acidic soils is maximum at the beginning gradually decreasing with time. The soils of moisture equivalents ranging 25-30% are most corrosive. Direct chemical corrosion has been found to be very predominant in acidic soil. |
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