Norizah Redzuan

Bio: Norizah Redzuan is an academic researcher from Universiti Teknologi Malaysia. The author has contributed to research in topics: Machining & Materials science. The author has an hindex of 7, co-authored 37 publications receiving 141 citations.

Machinability of nickel and titanium alloys under of gas-based coolant-lubricants (cls) - a review

Abstract: Advanced materials like nickel and titanium have un ique combinations such as low thermal conductivity, high chemical reactivity and hardness. All of these properties are desirable to be used as suitable lubricant and proper cooling technique for increasing tool life, decreasing cutting temperature and impro ving surface roughness. This paper presents a liter ature review done on gasbased coolant-lubricants (CLs) which used in the fo rm either gas or cooled-pressured gases. Investigat ion of previous researches with different approaches which have been used on m achining operation that effect on cutting temperatu re, tool wear and surface roughness. As a result, gas-based coolant-lubricant s (CLs) has been determined as one of the most suit able cooling process for machining cutting operation in terms of improvement in tool life and surface roughness. Furthermore, t his type of cooling process is considered as one of environmentally conscious m achining. Index Terms: Gas-based coolant‐lubricants (CLs), ni ckel and titanium alloys, tool wear, surface roughn ess and integrity, green machining.

Evaluation of sensitivity and calibration of the chaboche kinematic hardening model parameters for numerical ratcheting simulation

Abstract: Ratcheting failure of materials and structures subjected to low cycle fatigue in the presence of significant mean stress is of great interest to researchers. In this experimental and numerical study, the response of 316L stainless steel samples was observed in symmetric strain control uniaxial test followed by post-stabilized monotonic test, uniaxial and biaxial ratcheting tests, in order to determine the Chaboche model parameters and to evaluate ratcheting prediction using finite element analysis. The critical elastic limit was initially obtained from incremental uniaxial cyclic tests. The Chaboche parameters were subsequently extracted from experimental hysteresis and post-stabilized monotonic stress plastic-strain curves using two optimization technics, namely, the Particle Swarm Optimization (PSO) and Genetic Algorithm (GA). The two optimization methods were compared for efficiency, in terms of time and accuracy. The PSO method presented higher efficient results and was subsequently used to derive the parameters from hysteresis and post-stabilized monotonic curves. Different values (by definition) of elastic limit were also used. The Finite Element commercial software ANSYS was utilized with the Chaboche model to predict the uniaxial and biaxial ratcheting behavior of 316L stainless steel pipe. The comparison between experimental and the numerical simulation demonstrates that adopting post-stabilized monotonic curve rather than hysteresis curve and with accurate elastic limit obtained from incremental loading test improves ratcheting prediction significantly.

I and i

Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

Microwave Processing of Materials and Applications in Manufacturing Industries: A Review

Abstract: The main focused aim of developing new processing and manufacturing technologies are to reduce production or manufacturing costs, processing times, and to enhance manufactured product properties. The developed processing techniques should be widely acceptable for all types of materials including metal matrix composites, ceramics, alloys, and fiber reinforced plastics. Microwave materials processing is emerging as a novel processing technology which is applicable to a wide variety of materials system including processing of MMC, FRP, alloys, ceramics, metals, powder metallurgy, material joining, coatings, and claddings. In comparison to the conventional processes, microwave processing of materials offers better mechanical properties with reduced defects and economical advantages in terms of power and time savings. The present review work focuses mainly on global developments taking place in the field of microwave processing of materials and their relevant industrial applications.

Cryogenic Machining-Induced Surface Integrity: A Review and Comparison with Dry, MQL, and Flood-Cooled Machining

Abstract: The process of cryogenic machining, due to increased demand for environmentally friendly manufacturing processes, has seen a growing interest in the machining community. This article presents an overview of cryogenic machining and its induced surface integrity characteristics such as surface roughness, topography, grain refinement and machining-induced layer, microhardness, phase transformation, residual stress and fatigue life in machining of various materials including difficult-to-machine materials, aerospace alloys, lightweight materials, etc. The effect of cryogenic machining on surface integrity characteristics is discussed, and compared with dry, Minimum Quantity Lubrication (MQL), and flood-cooled machining processes. In addition to being an environmentally friendly process, this study shows that cryogenic machining significantly contributes to improved functional performance of machined components through its superior and more desirable surface integrity characteristics.