Brittle fracture, 2.20

Hydraulic piston-type compactors for collection vehicles, on-site compactors, and transfer-station compactors roll crushers used to fracture brittle materials and to crush tin and aluminum cans and other ductile materials... 

Primary deformation Ductile Ductile Brittle fracture Brittle fracture... 

Malleability and ductility These terms refer respectively to how readily a solid can be shaped by pressure (forging, hammering, rolling into a sheet) and by being drawn out into a wire. Metallic solids are known and valued for these qualities, which derive from the non-directional nature of the attractions between the kernel atoms and the electron fluid. The bonding within ionic or covalent solids may be stronger, but it is also directional, making these solids subject to fracture (brittle) when struck with a hammer, for example. A metal, by contrast, is more likely to be simply deformed or dented. 

Ductility is the plastic response to tensile force. Plastic response, or plasticity, is particularly important when a material is to be formed by causing the material to flow during the manufacture of a component. It also becomes important in components that are subject to tension and compression, at every temperature between the lowest service temperature and the highest service temperature. Ductility is essential for steels used in construction of reactor pressure vessels. Ductility is required because the vessel is subjected to pressure and temperature stresses that must be carefully controlled to preclude brittle fracture. Brittle fracture is discussed in more detail in Module 4, Brittle Fracture. 

The decrease of tensile strength and the increase of reduction in area with increasing test temperature can be related to changes in the fracture mode (Fig. 3.1-163), i. e., cleavage fracture, brittle grain boundary failure, and ductile transcrystalline failure [1.158]. 

Antimony (syn, stibium) [from the Arabic, aluthmud, the medieval Latin, antimoniunty originally applied to stibnite] (ICSD 64695 and PDF 35-732) Sb M= 121.75 Coordinence Sb(3) (Native elements) Trigonal (Rhombohedral) a =429.96 pm c= 1125.16pm A7, hR2 (Z = 6) P.G. 3m S.G. R3m oe-Arsenic type Uniaxial (n.a.) fjps 1.70-1.80 Rs 72.0-77.1% 3-3.5 (HV 83-99) 6660 Habit massive, lamellar, massive, reticulate. Color tin white. Diaphaneity opaque. Luster metallic. Streak lead gray. Cleavage (0001) perfect Fracture brittle. 

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