Layers bulk machining

Excimer laser micromachining at 248 and 193 nm was used as a flexible, standalone technique or in conjunction with photolithography and thermal molding to manufacture a bio-factory-on-a-chip device. Ghannels were generated in PC or PMMA, poly(dimethylsiloxane) (PDMS) membranes were thinned, and insulation layers between electrodes as well as encapsulation layers were machined [35]. Lin et al. [36] used UV excimer laser micromachining in bulk PI or PC substrates and... 

Abrasive processes inevitably lead to changes in residual stresses in both the surface layer and the bulk material. These changes in residual stresses are associated with form changes (distortion). Due to the impact on surface layer characteristics and on part precision, residual stresses play an important role in the manufactore and performance of the machined workpiece (Brinksmeier 1982 Brinksmeier et al. 1982). 

The surface characteristics of a microfluidic channel are very important in determining the flow in electrokinetically driven systems. In electrokinetically driven systems, the bulk flow is created by movement of the mobile diffuse layer near the channel wall/solution interface that is termed electroosmotic flow (EOF). The EOF is dependent on the surface of the microchannel walls. Roberts et al. demonstrated the generation of EOF on laser-ablated polymer substrates for the first time, using the parallel processing mode with a photomask and an ArF excimer laser at 193 nm [17]. A variety of polymer substrates such as polystyrene, polycarbonate, cellulose acetate, and poly(ethylene terephthalate) (PET) were ablated to fabricate microfluidic channels. The laser ablation process alters the surface chemistry of the machined regions and produced negatively charged. 

Some examples of the grain-size effect in ceramics are illustrated below Ti3SiC2 was chosen as one exemplar, since this ternary compound exhibits a unique combination of properties. It is a layered material that is as machinable as graphite. At the same time, CG (100-300 pm) samples of Ti3SiC2 have been observed to be damage-tolerant, not susceptible to thermal shock and oxidation resistant. The specimens are fully dense, bulk, single-phase polycrystalline samples of Ti3SiC2. This material exhibits brittle failure characteristics at RT, but is plastic at 1,300 °C with yield points of 300 and 100 MPa under compression and flexure, respectively. 

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