When subjected to alternating stresses, most materials degrade, e.g., suffer premature failure, due to a phenomenon known as fatigue. It is generally accepted that in brittle materials, such as ceramics, fatigue can only take place in toughened solids, i.e., premature fatigue failure would not be expected in materials such as single crystal silicon. The results of this study, however, appear to...

Surface and structural damage to plasma-facing components (PFCs) due to the frequent loss of plasma con®nement is a serious problem for the tokamak reactor concept. The plasma energy deposited on these components during loss of con®nement causes signi®cant surface erosion, possible structural failure, and frequent plasma contamination. Surface damage consists of vaporization, spallation, and li...

This paper presents a versatile model-free approach for linking the damage in highly heterogeneous materials at multiple scales. The proposed scheme evolves from phase-field modelling microscopic scale to simulate brittle failure, towards estimation of effective elastic, toughness and strength properties material mesoscopic scale, via coarse-graining technique. On one side, it’s shown that, com...

This paper reports ductile or partial ductile mode machining of silicon, glass and some advanced ceramics. Results are presented using scanning electron micrographs of the machined surfaces. Grinding and lapping operations using inexpensive machine tools could produce ductile streaks on surfaces of these brittle materials under good conditions. Manufacture of spherical glass lenses by the fract...

-A new configuration for compression-shear soft-recovery experiments is presented. This technique is used to investigate various failure mechanisms during dynamic multiaxial loading of an AI203/SiC nanocomposite and TiB2. Velocity profiles of the target surface are measured with a variable sensitivity displacement interferometer, yielding normal and transverse velocity-time histories. A dynamic...