Stress corrosion cracking aluminum content

Stress corrosion cracking (see also in Section 8.6 in pressurized ammonia vessels and tanks is a problem which has been discussed in many papers [1252]-[1265], [1271]-[1276], The mechanism of this phenomenon, the influence of water, and the role of oxygen are not yet completely understood, in spite of extensive research. A review is given in [1277]. As it is generally accepted that addition of water may inhibit stress corrosion [1263], [1264] it has become a widely used practice to maintain a water content of 0.2% in transport vessels [1264]. Protection may also be achieved by aluminum or zinc metal spray coating [1275], [1277], More recent research [1273], [1277], however, has shown that water may not give complete protection. 

Corrosion Properties. No data are available on the corrosion of Ti-17, but it should be susceptible to stress-corrosion cracking because its aluminum content is above 3 wt%. Corrosion of Ti-17 may be similar to Ti-6Al-2Sn-4Zr-2Mo given the comparable compositions. 

Ti-15-3 is expected to be less susceptible to stress-corrosion cracking (SCC) than T1-6A1-4V due to its hi vanaditun content and lower aluminum content. A phase stabilized by vanadium(or molybdenum, niobium, or tantalum) is immune to... 

Unalloyed titanium does not suffer stress corrosion cracking if the oxygen content is less than 0.3%. However, certain aluminum alloys are susceptible to SCC in specified environments (Table 9.51). 

Mg alloys that contain neither aluminum nor zinc are the most resistant to stress corrosion cracking (SCC). Aluminum content above a threshold... 

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