Khalid I. Alzebdeh

Bio: Khalid I. Alzebdeh is an academic researcher from Sultan Qaboos University. The author has contributed to research in topics: Finite element method & Micromechanics. The author has an hindex of 17, co-authored 45 publications receiving 897 citations. Previous affiliations of Khalid I. Alzebdeh include General Motors & Michigan State University.

Machinability of natural fiber reinforced composites: a review

Abstract: In the recent years with greater emphasis on the environmental and sustainability aspects of engineering materials, natural fiber reinforced composites (NFRCs) are gaining more importance because of their numerous advantages. Several researchers have developed NFRCs using various natural fibers as well as matrix materials. However, real-world applications of NFRCs require some secondary operations in order to complete the assembly of the components or parts. Very few researchers have discussed issues related to the machinability of these NFRCs. In this paper, for the first time, a comprehensive literature review on machining of NFRCs is discussed with focus on drilling operation. The paper also reviews the studies on milling and turning of NFRCs. The distinct feature of this review is that it identifies the factors that affect the quality of the machined feature and provides general recommendations for the selection of process parameters so as to generate better quality holes during drilling. In addition, the review also discusses the challenges that hinder machining of NFRCs which is a significant contribution to the field of NFRCs.

Scale and boundary conditions effects in elastic properties of random composites

Abstract: We study elastic anti-plane responses of unidirectional fiber-matrix composites. The fibers are of circular cylinder shape, aligned in the axial direction, and arranged randomly, with no overlap, in the transverse plane. We assume that both fibers and matrix are linear elastic and isotropic. In particular, we focus on the effects of scale of observation and boundary conditions on the overall anti-plane (axial shear) elastic moduli. We conduct this analysis numerically, using a two-dimensional square spring net-work, at the mesoscale level. More specifically, we consider finite “windows of observation”, which we increase in size. We subject these regions to several different boundary conditions: displacement-controlled, traction-controlled, periodic, and mixed (combination of any of the first three) to evaluate the mesoscale moduli. The first two boundary conditions give us scale-dependent bounds on the anti-plane elastic moduli. For each boundary condition case we consider many realizations of the random composite to obtain statistics. In this parametric study we cover a very wide range of stiffness ratios ranging from composites with very soft inclusions (approximating holes) to those with very stiff inclusions (approaching rigid fibers), all at several volume fractions.

Methods and apparatus for generating force and torque

Abstract: A system for providing support and position control of a monitor. In one embodiment, a method of supporting a monitor includes converting an ascending energy storage member force curve into a substantially constant supporting force against the monitor. In one aspect, a method, of supporting a monitor includes providing an energy storage member and a cam which are cooperatively positioned so as to move relative to each other along the path of motion. As the energy storage member moves along the path relative to the cam, the cam displaces the energy storage member and thereby changes a force applied by the energy storage member on the cam, and wherein the cam converts the force applied by the energy storage member into a supporting force on the monitor.

Lattice models in micromechanics

Abstract: This review presents the potential that lattice ~or spring network! models hold for micromechanics applications. The models have their origin in the atomistic representations of matter on one hand, and in the truss-type systems in engineering on the other. The paper evolves by first giving a rather detailed presentation of one-dimensional and planar lattice models for classical continua. This is followed by a section on applications in mechanics of composites and key computational aspects. We then return to planar lattice models made of beams, which are a discrete counterpart of non-classical continua. The final two sections of the paper are devoted to issues of connectivity and rigidity of networks, and lattices of disordered ~rather than periodic! topology. Spring network models offer an attractive alternative to finite element analyses of planar systems ranging from metals, composites, ceramics and polymers to functionally graded and granular materials, whereby a fiber network model of paper is treated in considerable detail. This review article contains 81 references. @DOI: 10.1115/1.1432990#