相关论文: Dissipation and plastic deformation in collisions …
The particle contact model is important for powder simulations. Although several contact models have been proposed, their validity has not yet been well established. Therefore, we perform molecular dynamics (MD) simulations to clarify the…
The impact of nanoparticles (NPs) comprised of atoms with covalent bonding is investigated numerically and theoretically. We use recent models of covalent bonding of carbon atoms and elaborate a numerical model of amorphous carbon (a-C)…
The surface impact and collisions of particle-laden nanodrops are studied using molecular dynamics computer simulations. The drops are composed of Lennard- Jones dimers and the particles are rigid spherical sections of a cubic lattice, with…
The kinetic friction and wear at high sliding speeds is investigated using the head-disk interface of hard disk drives, wherein, the head and the disk are less than 10 nm apart and move at sliding speeds of 5-10 m/s relative to each other.…
Simulation results for head-on collisions of equal-sized spherical polymer nanodroplets using molecular dynamics are presented. Elastic behavior of an initial compressed phase for the colliding droplets is analyzed. Deformations and contact…
The paper concerns the nanopowder high-speed, $10^4$ - $10^9$ s${}^{-1}$, compaction processes modeling by a two-dimensional granular dynamics method. Nanoparticles interaction, in addition to known contact laws, included dispersive…
The stress-driven motion of dislocations in crystalline solids, and thus the ensuing plastic deformation process, is greatly influenced by the presence or absence of various point-like defects such as precipitates or solute atoms. These…
We analyze the isotropic compaction of mixtures composed of rigid and deformable incompressible particles by the non-smooth contact dynamics approach (NSCD). The deformable bodies are simulated using a hyper-elastic neo-Hookean constitutive…
The current model of planet formation lacks a good understanding of the growth of dust particles inside the protoplanetary disk beyond mm sizes. In order to investigate the low-velocity collisions between this type of particles, the…
We report a new theory of dissipative forces acting between colliding viscoelastic bodies. The impact velocity is assumed not to be large, to avoid plastic deformations and fragmentation at the impact. The bodies may be of an arbitrary…
Aggregates consisting of submicron-sized cohesive dust grains are ubiquitous, and understanding the collisional behavior of dust aggregates is essential. It is known that low-speed collisions of dust aggregates result in either sticking or…
Nano-particle agglomeration plays an important role in processes such as spray drying and particle flame synthesis. These processes have in common that nano-particles collide at low concentrations and get irreversibly linked at the point of…
Contacts between particles in dense, sheared suspensions are believed to underpin much of their rheology. Roughness and adhesion are known to constrain the relative motion of particles, and thus globally affect the shear response, but an…
Tension-compression asymmetry is a notable feature of plasticity in bcc single crystals. Recent experiments reveal striking differences in the plasticity of bcc nanopillars for tension and compression. Here we present results from molecular…
Fissile nuclei with small shape distortion relative to the ground-state deformation and with low angular momentum were produced in peripheral heavy-ion collisions. Under the conditions of small shape distortions and low angular momentum,…
The contact mechanics of individual, very small particles with other particles and walls is studied using a nanoindenter setup that allows normal and lateral displacement control and measurement of the respective forces. The sliding,…
The static friction between crystalline surfaces separated by a molecularly thin layer of adsorbed molecules is calculated using molecular dynamics simulations. These molecules naturally lead to a finite static friction that is consistent…
The goal of this PhD thesis was to characterize the properties of friction in nanotubes and from a more general point of view the understanding of the microscopic origin of friction. Indeed, the relative simplicity of the system allows us…
Mechanical vibrations are known to affect frictional sliding and the associated stick-slip patterns causing sometimes a drastic reduction of the friction force. This issue is relevant for applications in nanotribology and to understand…
We simulate the collision of atomic clusters with a weakly attractive surface using molecular dynamics in a regime between soft-landing and fragmentation, where the cluster undergoes large deformation but remains intact. As a function of…