Strengthening brittle ceramics

Another reinforcement technique for strengthening concrete involves the introduction of residual compressive stresses into the structural member the resulting material is called prestressed concrete. This method uses one characteristic of brittle ceramics— namely, that they are stronger in compression than in tension. Thus, to fracture a prestressed concrete member, the magnitude of the precompressive stress must be exceeded by an applied tensile stress. 

Brittle materials, strengthening, 26 775 Brittle particles, ceramic-matrix composite reinforcement, 5 569—570 Brix hydrometer, 23 474 BRL-32872, novel antiarrhythmic agent, 5 106... 

Methods for mechanical testing of materials are briefly introduced along with various strengthening mechanisms. The number and siu-face area of the slip systems in metals and in ceramics are shown to be responsible for the ductility (or the lack of it) and for ductile-to-brittle transitions. Griffith s theory of brittle fracture is used to introduce fracture mechanics and to develop the concept of fracture toughness. The viscoelastic behavior of polymers is briefly discussed. 

Threaded inserts for use in brittle and flexible materials such as ceramics and plastics. Can be molded or cast in situ or inserted in previously threaded holes. Also Helicoil wire thread inserts for protecting and strengthening previously tapped threads. 

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