Azmah Hanim Mohamed Ariff

Nanomechanical Behavior of Multi-Walled Carbon Nanotubes Particulate Reinforced Aluminum Nanocomposites Prepared by Ball Milling

The nanomechanical properties of carbon nanotubes particulate-reinforced aluminum matrix nanocomposites (Al-CNTs) have been characterized using nanoindentation. Bulk nanocomposite specimens containing 2 wt % multiwalled CNTs (MWCNTs) were synthesized by a combination of ball milling and powder metallurgy route. It has been tried to understand the correlation between microstructural evolution particularly carbon nanotubes (CNTs) dispersion during milling and mechanical properties of Al-2 wt % nanocomposites. Maximum enhancement of +23% and +44% has been found in Young’s modulus and hardness respectively, owing to well homogenous dispersion of CNTs within the aluminum matrix at longer milling time.

Microstructural evaluation of ball-milled nano Al2O3 particulate-reinforced aluminum matrix composite powders

Abstract A mechanically alloyed mixture of Al-1 wt.% nano-alumina (n-Al2O3) composite powders was produced using a planetary ball milling machine. Different milling times were applied to investigate the effect of milling time on the dispersion and microstructure of n-Al2O3 particulate reinforcement within the aluminum matrix. A good homogeneous dispersion of n-Al2O3 particulates was observed after 8 h of milling. Longer milling times had no significant effect on the dispersion and morphology of n-Al2O3 particulates within the aluminum matrix because a steady state had been reached.

Factors Affecting the Porosity and Mechanical Properties of Porous Ceramic Composite Materials

In recent years, there has been an increasing interest in the study of porous ceramic composite materials. There are many products made of porous ceramic, such as membranes, catalytic substrates, filters, and others. This is due to their excellent properties in terms of high temperature stability, high permeability, excellent catalytic activity, and low bulk density. The purpose of this article is to review in detail the factors affecting the porosity of ceramic material, such as pore forming agents, the mechanical properties, and methods available to strengthen the material, such as sintering temperature, ceramic additives, and metal particle as additives and coating. Machining is also a concern regarding products made of ceramic materials since it is brittle in nature. Parameters optimized to improve machinability for ease of machining process were also discussed to address this concern.

Densification rate and interfacial adhesion of bilayer cemented tungsten carbide and steel

Abstract Manufacturing tailored materials is commonly faced with the challenge of shrinkage mismatch between layers resulting in delamination. The effects of sintering temperature and carbon variation on the densification and interfacial bond strength of bilayer cemented tungsten carbide and steel processed through powder metallurgy are analyzed. It is revealed through field-emission scanning electron microscopy images that inter-layer diffusion induced by liquid-phase sintering plays a major role in the densification and bonding of layers. Through dimensional analysis of sintered bilayer specimens, the strain rate of cemented tungsten carbide is observed to surpass that of steel. An enhanced densification rate of 6.1 % and M6C (eta carbide) reduction with increased carbon level results in strong interfacial bonding in specimens sintered at 1 280 °C. At 1 295 °C, diffusion accelerates and the axial and radial shrinkage increase by 14.05 % and 13.35 %, respectively, in 93.8 wt.% WC – 6 wt.% Fe – 0.2 wt.% C and 93.2 wt.% Fe – 6 wt.% WC – 0.8 wt.% C, thereby increasing the tendency for complete delamination.

Investigation of the Structure and Hardness of Quenched Sintered Materials Produced from Iron-Base Alloyed Powders (Astaloy E)

The effect of heat treatment on the microstructure, hardness and density of sintered (1129°C, 45 min) specimens of iron-base powder alloys containing 0.8 – 2.5% C, 2% Cu and additives of chromium- and molybdenum-alloyed Astaloy E iron powder is studied.

Vision Sensor Application for Intelligent Polishing Robotic Cell

Robotics especially on polishing process has not been exploited successfully in manufacturing, despite tremendous research efforts and potential needs in industries. There is still much concern on how robots are used in industries and stumbling blocks in the deployment of technology. In this study, the techniques to alleviate difficulties in using robots and deploying advanced technologies in the real manufacturing environment will be developed. However, the mirror polishing process still depends on human expert, compared to CNC and CAD/CAM technology. On top of that, undesirable working condition exists due to dust and noise. Next, it is quite difficult to find skilled technicians where existing industrial robot (normally with repetitive accuracy of 0.1mm) not suitable for mirror polishing task requirement (10nm). This study addresses idea to develop and automate the polishing process by using robots. It applies specifically on flat steel surfaces and the image of the workpiece is captured by vision sensor. The image captured is extracted to develop ANFIS (Adaptive Neuro Fuzzy Inference System) to determine the roughness so that correct polishing parameter will be applied on the surface of the workpiece when polishing is done. ANFIS is well suited to the management of uncertainty, is introduced to address the uncertainty problem associated with surface roughness.