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The creation of nanostructured materials with enhanced mechanical properties by controlled chip formation has been demonstrated. The present study examines the microstructure and mechanical properties of chips from various alloys -Waspaloy AMS 5704, Inconel 718, Al 6061-T6, and titanium - produced in aerospace machining operations. While the deformation conditions with respect to chip formation may be ‘less than controlled’ in these cases, it is nevertheless seen that the chips created are composed entirely of nanocrystalline structures of high hardness and strength. The microstructural characteristics and properties of these chips are compared and contrasted with those produced under controlled conditions of strain and temperature. The results suggest that aerospace machining chips can be up-scaled as high-performance structural materials with substantial cost benefits.

Extensive experimental data was collected for CBN surface grinding of M2 tool steel to determine the relative grinding performance of three different vitrified CBN abrasive grit sizes. The results define the relationships between the grinding forces, the material removal rate and the resulting specific energy, while providing an evaluation of the ground surface characteristics including surface finish, microstructure, hardness and residual stress. The interaction of grinding process inputs including wheel grit size, workpiece velocity and depth of cut are considered, and a series of single factor tests and a 23 factorial test are conducted. The grinding forces increase linearly with increasing material removal rate for the range of parameters tested.