Incipient plasticity in 4H-SiC during quasistatic nanoindentation

Abstract

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Twinning anisotropy of tantalum during nanoindentation

“…Normally, pyramidal indenters, such as Berkovich or cube corner, are classified as ''sharp'' indenters while spherical indenters are referred to as ''blunt'' indenters [3]. In practice, almost all indenters have some finite edge radius (despite being referred to as extremely sharp) and therefore a spherical shaped indenter was deployed (figure 2a) during the simulation to mimic an indenter with a finite edge radius.…”

“…Nanoindentation of metals in particular, involves plastic deformation due to several competing mechanisms such as nucleation and motion of dislocations, deformation twinning and grain boundary sliding (a subset of slip mechanics) [3].…”

Can a carbon nano-coating resist metallic phase transformation in silicon substrate during nanoimpact?

“…Depending on the depth of the impact, energy transferred from the indenter to the coating and the stresses induced during the process may result in a backward (negative) depth deviation [6]. Further work in this direction can be referred elsewhere [6,23].…”

Advances in the surface defect machining (SDM) of hard steels

“…Of particular importance in this regard is the fact that the ASTM standard recommends the surface roughness value (Ra) on the metallic knee joint implants to be lower than 100 nm [46]; this was obtained with ease during this study. Furthermore, although ceramics such as silicon carbide are preferred choice over steels [47,48] for such advanced biomedical applications, stainless steel is still used in practice and this work demonstrates that there is the potential to use hard turning to machine such precise components.…”