Environment-sensitive cracking

Environment Aluminum alloys Carbon steels Copper alloys Nickel alloys Stainless steels Austenitic Duplex Martensitic Titanium Zirconium alloys alloys 

Evaluation of susceptibility to environment-sensitive cracking encounters the usual problems of attempting to simulate in the laboratory conditions that reflect service performance. Two approaches are usually taken, both of which must provide a final consistent prediction of service behavior. One of these approaches is to duplicate as closely as 

A wide variety of test conditions, and particularly specimen geometries, have been used in establishing standard tests and in research on environment-sensitive cracking. Representative examples of test specimens are shown in Fig. 7.69 (Ref 109). A number of considerations enter into the choice of test specimen  

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While ideally structures should be designed and fabricated so that environment-sensitive cracking is avoided, in practice it is sometimes necessary to live with the problem. This implies an ability to detect and measure the size of cracks before they reach the critical size that may result in catastrophic failure. Such inspection has important implications for plant design, which should be such as to allow inspection at relevant locations. The latter are regions of high residual stress (welded, bolted or riveted joints) and regions of geometrical discontinuity (notches, crevices, etc.) where stress or environment concentration may occur. 

Stewart, A. T., Effect of hydrogen on fatigue crack propagation in steels , Proc. Int. Conf. on Mechanisms of Environment Sensitive Cracking in Materials, University of Surrey, 4-7 April 1977, The Metals Society, pp. 400-11 (1977)... 

This paper was presented at the International Conference on Environment-Sensitive Cracking Mechanisms and Industrial Applications, which was held at Guilin, China, 4-9 September 1994. 

Relationship of Composition and Heat Treatment to Environment-Sensitive Cracking of Aluminum Alloys. Those aluminum alloys strengthened by cold working only, particularly the 1000-series alloys, do not develop susceptibility to SCC. The so-called high-strength alloys are strengthened by thermal/mechanical treatments, which result in solid-state precipitation of one or more intermetallic phases that restrict dislocation motion and, hence, increase strength. Their susceptibility to SCC varies extensively with alloy composition and the thermal/mechanical treatment. While susceptibility tends to increase with... 

The major variables in fracture-mechanics investigations of environment-sensitive cracking under cyclic loading include (Ref 163, 168) ... 

Swann, P.R., Ford, F.P. and Westwood, A.R.C., "Mechanisms of Environment Sensitive Cracking of Materials," Metals Society, London, 1977. 

A Yamamoto et al., Proc. of 2" Inti. Conf. on Environment Sensitive Cracking and Corrosion Damage,Nishika Printing, Hiroshima, Japan, pp. 160-167, 2001. 

R.N. Parkins, Y. Suzuki, Environment sensitive cracking of a nickel-aluminum bronze under monotonic and cyclic loading conditions, Corros. Sci. 23 (1983) 577-599. 

Kambour, R. R, in Proceedings of the International Conference on the Mechanics of Environment Sensitive Cracking Materials, University of Surrey, Guildford, UK 1977, p. 213. 

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