Critical crevice corrosion temperature

Crevice corrosion is, of course, dependent on temperature. No crevice corrosion is found to occur below a certain temperature called the critical crevice corrosion temperature, which is similar to the critical pitting temperature mentioned earlier. The critical crevice corrosion temperature has been used as a measure to evaluate metallic materials for the susceptibility to crevice corrosion [63],... 

Figure 10.4 Critical pitting temperature (CPT) and critical crevice corrosion temperature (CCT) for various stainless steels in 6% FeCb solution [10.9]. The figures below the columns show the contents of Cr, Ni and Mo, respectively (compare Tables 10.5 and 10.6).

CCT Critical crevice corrosion temperature HAZ Heat-affected zone... 

To overcome these limitations. Method D measures the critical crevice corrosion temperature, using a multiple crevice assembly (MCA). The test solution is 6 wt. percent FeCl3 acidified with 1 wt. percent HCl. This test method is also referenced in ASTM G 157 for evaluating the corrosion properties of wrought iron- and nickel-based corrosion resistant alloys for the chemical process industries. 

AHoy/Laboratoiy Method C—CPT Critical Pitting Corrosion Temperature (C) Method D—CCT Critical Crevice Corrosion Temperature (C) ... 

The materials Monit and Sea-Cure are characterised by good resistance to pitting, crevice and stress corrosion cracking in seawater. The critical pitting corrosion temperature in the FeCls test is 328 K (55 °C) and the critical crevice corrosion temperature is 318 K (45 °C). In Table 36, the pitting potentials of the two superferrites and the austenitic steels 1.4539 (SAE 904 L, XlNiCrMoCu25-20-5) and X3CrNiMol7-13-3 (SAE 316,1.4436) measured in 5% NaCl solution are presented. 

The critical crevice corrosion temperature of an alloy is the temperature at which crevice corrosion is first observed when immersed in a ferric chloride solution. Table 1.3 lists the critical crevice corrosion temperature of several alloys in 10% ferric chloride solution. 

Critical Crevice Corrosion Temperature for the Duplex and some Austenitic Stainless Steels In 101 FeCl3-6H20 (pHl) ... 

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