Structural materials damage

Helium embrittlement is another structural material damage mechanism. Helium is produced in (n,a ) reactions. Trace quantities of boron and nitrogen in structural materials can make a significant contribution to the helium production. Consideration must also be given to (n,a) reactions in isotopes which are formed as a consequence of irradiation for example Ni-58 (n,y) Ni-59 (n,a)... 

In general, molecular crystals are too soft for them to be of interest as structural materials. Also, they fracture readily. Because of their transparencies and non-linear properties some of them are of interest for optical applications, but most of them suffer from optical damage at low intensities of light. 

The intensity of seismic motion that can be tolerated by various kinds of structures must be established before acceptable charge weights at various distances can be determined. Obviously, the level of motion required to damage a structure depends upon its construction. For example, a steel-framed warehouse can tolerate a more. intense seismic wave than a residential structure with plaster walls. Because plaster is the weakest of the most commonly used materials of construction, and because of the prevalence of such structures, most damage criteria are based oh this type of structure... 

The extrusion curve for these materials hardly shows any release of mercury and reintrusion experiments exhibit a negligible intrusion, indicating the original hexagonal porous structure is damaged and as a consequence these materials are inappropriate as model materials in MIP. 

In confined spaces where spills, overflows or some leakage may occasionally occur, or where the ambient conditions are mildly corrosive, wood will not be seriously or rapidly affected by mild acids and some other liquids which would damage other structural materials extensively. 

Sulfur dioxide is corrosive it damages plants, structural materials, and humans. It is a nasal, throat, and lung irritant. Sulfur dioxide is slowly oxidized to sulfur trioxide, SO3, hy oxygen in air ... 

Ecole des Mines (Center for Materials Science and Structures), Plasticity, Damage and Corrosion of Materials CNRS Laboratory, Saint-Etienne, France... 

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