Slip in Ceramics

In metals, slip and the common slip systems are usually discussed in terms of the various structures of single crystals BCC, FCC and HCP. There is no basic difference between the slip systems in ceramics (or other crystalline materials) and metals, since all the aforementioned structures appear in both materials. Thus, NaCl, MgO, CaO, KBr, etc. have an FCC structure with a primary 110 (110) slip system. jS-SiaNq is HCP with a (1120) (0001) slip system. a-SisNq with (0001) (llIO) and (0001) (1120)and fl-SiC cubic (zincblende) with a 111 (110) slip system. However, unlike pure metallic systems (see Fig. 4.22a), ceramic FCC 

An illustration of slip lines in MgO (having a rocksalt structure is shown in Fig. 4.23. The specimens cleaved along the 100 planes were tested at RT under compression along (100) with an Instron machine using a deformation speed of 0.06 mm/min. The deformation results appear in Fig. 4.24. 

Molybdenum disilicide (MoSi2), an intermetallic compound, a silicide of molybdenum, is a refractory ceramic primarily used in heating elements. It has 

There are controversies regarding the slip systems in MoSi2. Mitchel et al. [38] did not find 1/2 (331) dislocations in deformed single crystals and they stated that the presence of such dislocations are either unstable or they occur under special conditions of orientation, temperature and stress state. 

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