Laser-Induced Controlled Flaw Testing in Ceramics

摘要

The present investigation yields significant results in controlling crackformation in transparent ceramic crystals (LiF, MgO, ZrO2, and Al2O3), as well as in amorphous solids (fused quartz and PMMA) through a series of systematic experimentations and theoretical modeling of the laser-solid interaction. The impact of such success is the extension of another dimension in the investigation of many mechanical and physical problems from the current two-dimensional simplifications to three-dimensional phenomena. The critical control of the formation of internal cracks allowed us, for the first time, to examine the interaction of three-dimensional cracks in PMMA and fused quartz, and to validate the general predictions of the available theoretical analyses. We also studied the interaction of a penny-shaped internal crack and dislocations in lithium fluoride single crystals, a phenomenon currently under renewed extensive investigation for fundamental understanding of the ductile vs. brittle behavior of solids.