Impact Angle Of Incidence Research Articles

Development of a Deposition Strategy in Cold Spray for Additive Manufacturing to Minimize Residual Stresses

Cold Spray (CS) is a rapidly developing metal deposition technology, which allows for the formation of coating layers in a melt-free manner and is starting to replace existing technologies at industrial level. New developments in the field of CS as well as optimization of spraying strategy permit to elaborate freeform 3D objects with reasonable precision. Residual stress is among the most important factors affecting coating integrity in fact they can lead to peeling and/or delamination of coatings. In this study two different types of simulation were performed: at the microscale, using ANSYS-AUTODYN, a high impact simulation in order to study the mechanism of formation of residual stress in the cold-sprayed deposited particle; and at the macroscale a static structural simulation based on Tsui and Clyne's progressive deposition model in order to investigate a possible interaction between different layers and developing a deposition strategy. For the first time, in this work, a parametric study of the single impact particle to study the residual stress was proposed finding that impact velocity; incident angle of impact and density and the yield stress for the materials involved in the deposition have a strong influence in the residual stress formation. Furthermore, at a macroscopic scale, a deposition strategy that minimises residual stress was identified. In fact, it was found that the deposition of successive layers with a perpendicular relative orientation leads to a final product with lower residual stress.

Spatial Impact of a Slender Beam

In this paper, the dynamics of the spatial impact of a slender beam is analyzed. The equations of motion are calculated using Kane’s impact method. The generalized momentum and generalized impulse of the beam are considered to find the equations of motion of the beam. The frictional phenomenon at the contact point is analyzed. For the case of impact without slipping, it is used the assumption that the tangential component of the velocity of separation is null. In the case with slipping, the tangential impulse (at the plane of impact) is computed. The sliding direction after impact is calculated. A simulation of the impact of beam with a surface is developed and the velocity of separation, force of impact and kinetic energy of the beam after impact are studied for different incident angles of the beam. The incident angle is varied from 0 deg to 57 deg. The results are function of the incident angle of impact.

Simulation for the Oblique Impact of a Lattice System

The oblique collision between an elastic disk and an elastic wall is numerically studied. We investigate the dependency of the tangential coefficient of restitution on the incident angle of impact. From the results of simulation, our model reproduces experimental results and can be explained by a phenomenological theory of the oblique impact.

Molecular dynamics simulation of reactive ion etching of Si by energetic Cl ions

We report results from molecular dynamics simulations of the etching of a Si surface by energetic Cl atoms (15 eV⩽E⩽200 eV). We find that the energy dependence of the Si yield (number of Si atoms desorbed per incident Cl ion) is in reasonable agreement with recent experiments and with previous simulations performed up to 50 eV. We also investigate the variation of the Si yield with the impact angle of incidence, the stoichiometry of the desorbed material, and the effect of a thermal background Cl flux to the surface in the presence of an ion flux at 50 eV. Surface roughening due to etching was observed and the calculated rms roughness is in reasonable agreement with experiments.