Delamination is one of the most concern defects in drilling of composite material. Delamination depends on the factors such as feed rate, tool geometry and wear. The mechanics of drilling composite materials has been examined along with the quality of the hole and the effect of tool design parameters. The capacity of computerized tomography (CT) showing sample cross-section in a nondestructive ...

The characteristics of carbon fibre reinforced plastics allow a very broad range of uses. Drilling is often necessary to assemble different components, but this can lead to various forms of damage, such as delamination which is the most severe. However, a reduced thrust force can decrease the risk of delamination. In this work, two variables of the drilling process were compared: tool material ...

Friction drilling uses a rotating conical tool to penetrate the workpiece and create a bushing in a single step without generating chips. This research investigates the threedimensional (3D) finite element modeling (FEM) of large plastic strain and hightemperature work-material deformation in friction drilling. The explicit FEM code with temperature-dependent mechanical and thermal properties, ...

Cutting tools are widely used in manufacturing processes and drilling is the most commonly used machining process. Although drill-bits used in drilling may not be expensive, their breakage can cause damage to expensive work piece being drilled and at the same time has major impact on productivity. Predicting drill-bit breakage, therefore, is important in reducing cost and improving productivity...

SUMMARY The use of composite laminates in complex structures has increased significantly. However, there are still some issues when considering their use, mainly related with machining, leading to some difficulties and lack of acceptance. In this work, a methodology to evaluate drill geometry and feed rate based on thrust force and delamination extension is presented. INTRODUCTION For the past ...

In this paper, a new design of permanent magnet linear synchronous motor (PMLSM) for electromagnetic launcher system (EMLs) has been investigated in terms of the requisite amount of average launching thrust force and thrust force ripple minimization through finite element method. EMLs are a kind of technology used to develop thrust force and launch heavy loads with different applications includ...

The distinguishing characteristics of carbon fibre reinforced laminates, like low weight, high strength or stiffness, had resulted in an increase of their use during the last decades. Although parts are normally produced to “near-net” shape, machining operations like drilling are still needed. In result of composites non-homogeneity, this operation can lead to delamination, considered the most ...

Drilling is the most frequently employed operation of secondary machining for fiber-reinforced materials owing to the need for structure joining. Delamination is one of the serious concerns during drilling. Practical experience shows that an eccentric twist drill or an eccentric candle stick drill can degrade the quality of the fiber reinforced material. Comprehensive delamination models for th...

This study aims to optimize drilling variables reduce the thrust force required for composite materials. The optimization process involves using evolutionary algorithms such as particle swarm (PSO) and genetic algorithm (GA) determine best combination of parameters, including drill speed, feed rate, point angle. objective is minimize while maintaining desired quality drilled holes. ANOVA regres...

An innovative Kirschner (K-) wire point was developed and compared in fresh pig femora in terms of drilling efficiency and temperature elevation with the trochar and diamond points currently used in clinical practice. The tips of thermal couples were machined to the defined geometry and the temperature measured during drilling. Using the same drill speed (rev/min) and feed rate, the new K-wire ...