Corrosion table

Cast lead—calcium—tin alloys usually contain 0.06—0.11 wt % calcium and 0.3 wt % tin. These have excellent fluidity, harden rapidly, have a fine grain stmcture, and are resistant to corrosion. Table 4 Hsts the mechanical properties of cast lead—calcium—tin alloys and other alloys. 

The cupro-nickel alloys (5-30% of nickel) are perhaps the best of all for strength and resistance to corrosion. Table 3.20 gives typical properties. 

Friend show the superiority of Fe-36Ni over mild steel with respect to both average and localised corrosion (Table 3.31)... 

Corrosion Tables of Special Materials and Rare Metals, Jacob and Korves GmbH... 

ECONOMIC ASPECTS OF CORROSION Table 9.2 Comparative schemes for protecting steelwork (27-4 m /t)... 

The available range of plastics is very wide with a variety of compositions and related properties within any one type description. Even when physical properties and formulation are specified, minor variations in trace additives, release agents, moulding cycles, etc. may have a considerable influence on corrosivity. Table 18.18 can therefore be considered only as a guide and even in this sense much more experimentation is needed to provide the full picture. In the present state of technology precise information is only likely to result from tests carried out on the material of interest various suitable test methods have been described in the literature ... 

Little comprehensive work has been carried out on contact corrosion, but some results on a range of polymers have been reported by Czech workers". In general, plastics that give rise to vapour corrosion (Table 18.18) will also cause contact corrosion. Some qualification is needed to this statement, however, as much depends on the type of contact and the other ingredients in the polymer, e.g. a paint may give good protection to the metal to which it is applied, but the vapour may cause corrosion of adjacent metal items within an enclosed space. 

In a corrosive medium, metals and metal alloys form reaction products which are stable and similar to those found in nature. Loss of metal in this manner is uniform over the surface and can be measured. Standard corrosion tables contain this type of information. 

Resistance to fluid corrosion is by far the most important aspect This topic is discussed in detail in the mentioned references, where extensive corrosion tables are given. From this point of view process fluids can be classified as follows ... 

Pitting corrosion (Table 4.8) involves pit initiation (breakdown of passive film) followed by pit growth. The chloride ion induces pitting corrosion. Type 304 steel undergoes pitting more readily than Type 316 steel. The molybdenum in 316 steel is responsible for its reduced susceptibility to pitting corrosion. Type 316L steels contains... 

The analysis of experimental data shows that the average value 111 g/m2 of all corrosivity data (improved by rejecting outliers) corresponds to the value 140 40 g/m2 indicated in the standard. For the evaluation of the expanded combined uncertainty U with factor k=2 the corrosivity measurement gives the value of 215 g/m2 (at 95% confidence). It means that our data uncertainty is five-times higher than that specified in the standard as the data scattering interval 40 g/m2 and seven times as wide compared the statistic confidence interval in our own experimental data corrosivity (Table 2a and 2b). The main components of the combined uncertainty are mass loss and surface area determination. 

Materials and Corrosion, Surface Area Protection in Advanced Chemical Engineering], 1952 -53, 386 and 1954- 55, p. 560. F. Ritter, Korrosions-tabellen metallischer Werkstoffe [Corrosion Tables of Metallic Raw Materials], Vienna, 1944. 

The inhibited polymer films may simultaneously present a barrier for electrochemical and microbiological corrosion. Table 2.11 and Fig. 2.43 illustrate data from [5, 6, 54] characterizing the capability of PE films containing Cl of the PHC series to inhibit vitality of microscopic fungi and bacteria whose metabolic products evoke corrosion damage of metals. 

General corrosion is the most common form of corrosion. This can be uniform (even), quasi-uniform, or uneven. General corrosion accounts for the greatest loss of metal or material. Electrochemical general corrosion in aqueous media can include galvanic or bimetallic corrosion, atmospheric corrosion, stray current dissolution, and biological corrosion (Table 1.1). 

Some of the considerations that play a role in deciding on rehabilitation or replacement of a pipeline are terrain conditions, expected or required life, excess capacity, throughput requirements, and internal versus external corrosion (Table 4.23). 

By providing education and training on corrosion control and prevention to plant personnel at all levels, it should be possible to control and prevent corrosion. Table 4.36 is a summary of issues that need attention. 

Selection of material. As dealt with in previous sections, conventional stainless steels, with martensitic, ferritic, austenitic or ferritic-austenitic (duplex) structure, are sensitive to crevice corrosion (Table 7.4). Newer high-alloy steels with high Mo content show by far better crevice corrosion properties in seawater and other Cl-containing environments (see Section 10.1). 

Corrosion Tables of Stainless Steels. Stoekholm Jemkontoret, 1979 (in Swedish). 

The corrosion tables on the following pages are arranged alphabetically according to the corrodent. The chemicals listed are in the pure state or in a saturated solution unless otherwise indicated. Compatibility is shown to the maximum allowable temperature for which data is available. Incompatibility is indicated by an x. A blank space indicates that data is not available. 

Ritter, F. (1958). Korrosionstabellen metallischer Werkstoffe (Corrosion tables for metallic materials), 4th ed., Springer-Verlag, Vienna (in German), 290 pp. 

There are a number of tests available for the evaluation of the sensitivity of a given stainless steel to intergranular corrosion (Table 7.41). They differ in severity of corrosion conditions and therefore do not reveal the same phenomena. The oxalic acid test consists of an electrochemical attack at constant current. The morphology of the corroded surface is then compared with reference samples. The main advantage of this technique is its rapidity (the attack takes about one minute). The applied potential lies in the transpassive region, where the chromium easily dissolves. The oxalic acid test therefore does not reveal the zones depleted in chromium, but rather exposes the presence of carbides and intermetallic phases. 

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