In the search for improved mechanical properties, researchers have explored the region of finer and finer microstructural features in recent years. Much of the early interest in increasing the strength of polycrystalline materials by reducing the grain size arose from the Hall-Petch relationship [1,2] which indicates that the flow stress should be inversely proportional to the square root of the grain diameter. The original treatments of Hall and Petch were based on models of the stress concentration produced by a pileup of dislocations at a grain boundary.

Mechanical Properties and Deformation Behavior of Nanostructured Ceramics

A brief study of the microhardness of nanocomposite coatings fabricated by a new technique is reported. The new fabrication technique utilizes sputtering at high pressures in a thermal gradient to produce nanometer-size particles, which are then embedded in a matrix produced by conventional sputtering. The microstructures and microhardness of nanocomposite coatings of Al matrix reinforced by Mo particles (grain diameter ranging from 7 to 20 nm) are reported.

C. Cm. Wu

Papers

Mechanical Properties of Nanocomposite Coatings Fabricated by Sputttering