Hydrogen embrittlement describes a group of phenomena leading to the degradation of metal ahoy properties. The hydrogen concentration in the ahoy can be used as an indicator for the onset of embrittlement. A neutron tomography system has been optimized to perform nondestructive detection of hydrogen concentration in titanium aircraft engine compressor blades. Preprocessing of backprojection ima...

When subjected to extended exposure to intermediate service temperatures, Cr–Mo steels, Ni–Cr steels, and 5% Ni steels can become embrittled, with an associated decrease in fracture toughness and a shift in the ductile-to-brittle transition temperature to higher temperatures. Two methods for the investigation of temper embrittlement phenomena are isothermal aging or the use of a step cooling ag...

Usually, materials are inspected by nondestructive methods to detect and evaluate defects that may cause failure under the designed operation conditions. However, the structure may also fail due to uncertainties of material properties like strength or hardness, and may also suffer from unexpected degradation during operation. A reliable NDE technique for detecting the inception of failure durin...

While hydrogen embrittlement of ferritic steels has been a subject of significant research, one of the major challenges in tackling hydrogen embrittlement is that the mechanism of embrittlement is not fully resolved. This paper reports new observations and interpretation of fracture surface features and deformation microstructures underneath the fracture surface, providing a mechanistic view of...

in this paper, the hydrogen embrittlement of the high strength cr-si spring steel with after zn-12%ni electroplating, have been evaluated. slow strain rate test with 3.34 × 10 -6 sec -1 strain rate was performed, and the hydrogen embrittlement index of the different samples was calculated. the effect of shot peening before plating and the baking after plating and also the effect of applying a n...

The critical energy release rate defined as Gc = 2γ + γp (where, γ is the cohesive energy and γp is the plastic work) is widely used as a macroscopic fracture criterion. During embrittlement of Aluminum by Gallium, impurity segregation is localized to a small region along the grain boundary and the bulk plastic properties is unaffected. Yet, the critical energy release rate (which is predominan...

The Cu-Bi system exhibits nearly no solubility of Bi in Cu along with the highest solute boundary enrichment factor among metal systems making the Cu-Bi system ideal for segregation studies [1]. Cu-Bi also shows a high degree of segregation induced grain boundary embrittlement. The precise cause of this embrittlement has been attributed to Bi size effects along the Cu boundary or modification o...

The resistance to hydrogen embrittlement is of essential importance for steels for vessels for storage of hydrocarbons and depends on the effect of absorbed hydrogen on steel ductility. API tests have shown for the 490 MPa yield stress HSLA steels with the microstructure of ferrite and cementite particles a much greater reduction of area than for the 350 MPa steel with the microstructure of pol...

iii Abstract: High manganese TWIP (TWinning Induced Plasticity) steels are particularly attractive for automotive applications because of their exceptional properties of strength combined with an excellent ductility. However, as austenitic steels, they appear to be sensitive to liquid zinc embrittlement during welding, the liquid zinc arising from the melted coating due to the high temperatures...

7bis report presents a procedure for estimating the current condition and residual life of -safety-related cast stainless steel components in light wa racos (LWRs). The procedure accounts for loss of fractur toughness caused by hrmal embrittlement and includes the folloing: a review ofdesign and fabrication records, nserice inspection recods, and operating history a fracture mechanics evaluatio...