Precipitation-hardenable steels cracking

The martensitic and precipitation-hardening stainless steels are more susceptible to hydrogen embrittlement than are the austenitic alloys. The susceptibility of these stainless steels is sensitive to microstructure and strength level. Figure 22 shows the resistance to cracking for a martensitic (type 410) stainless steel and some precipitation-hardening stainless steels in an H2S-saturated solution [174]. The low resistance of type 410 stainless steel is typical for most... 

Intergranular hydrogen cracking in a precipitation-hardening martensitic stainless steel has been suppressed by the addition of palladium. Heat treatment of the alloy produces submicrometer-sized PdAl precipitates that act as reversible traps and are thought to reduce the amount of hydrogen at prior austenite grain boundaries [134]. 

R. R. Gaugh, Sulfide stress cracking of precipitation-hardening stainless steels. 

The precipitation-hardened variants (PH steels) are used in seawater in cases in which higher strengths are required. Due to their much lower corrosion resistance levels, they require cathodic protection. It must be remembered that at potentials more negative than Uh = -0.85 V these steels must be expected to show stress corrosion cracking [114,138,139]. 

The austenitic stainless steels resist hydrogen effects, but martensitic and precipitation-hardening alloys may be susceptible to both hydrogen stress cracking and chloride stress cracking. 

Gaona-Tiburcio G, Almeraya-Calderon E, Martin -Villafane A, Baustista-MaiguUs R (2001) Stress corrosion cracking behaviour of precipitation hardened stainless steels in high purity water environments. Anti-corrosion Methods Materials 48(1) 37-46 Bacteria could help control corrosion at power plants (1998) Mater Perform 37(11) 50-51 Cost of corrosion study update Trends in the automotive industry (2000) Mater Perform 39(8) 104-105... 

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