Experimental and numerical studies on superhigh strengthening sintered low alloy steels fabricated by metal injection molding)

Metal injection molding (MIM) process is an advanced powder processing technique because of net shaping with shape complexity at low processing energy and 100 % material utilization. This study has been performed to clarify and to optimize the relationship between the mechanical properties and the microstructures for obtaining the superhigh strengthening sintered low alloy steels (Fe-Ni system) by using MIM process. The influence of nickel particle sizes, nickel content, and sintering conditions on the microstructure and mechanical properties of superhigh strengthened Fe-Ni steel compacts have been systematically investigated. As starting materials, the mixed elemental of carbonyl iron and water-atomized nickel powders were utilized. Tempered compact added 6 mass% fine nickel powder followed by sintering at 1250 °C for 1 hour showed superhigh strength of 2040 MPa with elongation of 8.1 %, which was the best properties among reported data in P/M low alloy steels so far. These excellent mechanical properties is due to the fine heterogeneous microstructure consisted of nickel rich phase surrounded by a networks of tempered martensitic structures. The mechanical properties of MIM compacts are highly dependent on two major factors; the porosity, and the microstructural morphology in the matrix. Both factors were cautiously considered in the present work. The porosity studies was carried out on 440C sintered steel, which was a high strength material with numerous pore contents. For the latter, the superhigh strengthened Fe-Ni steel compact, which is a primary alloy steel in this study was employed for microstructural studies on the matrix. Not only experimental work but also numerical simulation by finite element method was engaged to understand how these factors work. 440C steel compact has been purposely used as an example material to examine the pore factor. The utilization of 440C steel compact was due to homogeneous microstructure of matrix although contained many residual pores. The porosity study begins with experimental works, followed by numerical simulation for verification. The model demonstrated that tensile properties was enhanced at reduced pores and depreciated when the porosity was increased. Also, when mechanical properties of the compacts with similar porosity level is compared, the pore factor can be disregarded due to their minimum influences. However, the pores became a major factor when comparing compacts of different porosity levels. After the pore factor was successfully tested and evaluated, the effort had extended to the core focus of the present study. The effect of heterogeneous microstructure was treated in order to evaluate superhigh strengthened Fe-Ni steel compacts. Sintered density of all Fe-Ni steel compacts obtained in this study was 95-96 %, it means the porosity levels were about similar. Therefore, the pore factor has been simply omitted. The microstructure of all superhigh strengthened Fe-Ni steel compacts have been consistently structured by heterogeneous condition. The microstructural heterogeneity aspects of the compact were changed by the characteristics of Ni powder, such as particle size, shape, and content, which play important roles in the deformation behavior. A complex network of higher Ni region which firmly bounded by the lower Ni region (matrix region) has been comprehensively observed. The high ductility and high strength offered by the superhigh strengthened Fe-Ni steel compacts were probably also due to mechanically induced martensitic transformation that takes place during deformation. The material was initially metastable retained austenite, which was relatively ductile phase and the ductility was enhanced by the martensitic transformation-induced plasticity (TRIP) phenomenon. The high strength was due to the transformation of the soft austenite phase to the hard martensitic phase during the deformation as experimentally observed. In order to understand how the microstructure results these high mechanical properties, finite element modeling based on the spatial distribution obtained experimentally was developed. Some parameters were prepared to control heterogeneity in the representative volume element. The simulated results were compared to experimentally obtained behavior, and showed good agreements. These capabilities of successful simulation of the actual microstructure by FEM resulted possibility to identify and design an optimum microstructure theoretically for Fe-Ni system

A Global Outreach by two Malaysians Success Story Unveiled

Universiti Malaysia Pahang (UMP) received the Qatar National Research Fund (QNRF) worth RM350,000 from a total of RM3.2 million in 2016 by Associate Professor Ts. Ir. Dr. Kumaran Kadirgama and Associate Professor Ts. Ir. Dr. Wan Sharuzi Wan Harun. The grant is a collaboration with Qatar University, Hamad Medical Corporation, and Rutgers University. The achievement of the project shows that Universiti Malaysia Pahang can compete with other universities in the world

Pilihan laluan jurutera profesional di Malaysia A, B atau C

Menjadi jurutera profesional di Malaysia melibatkan lebih daripada pencapaian akademik atau kemahiran teknikal; ia juga tentang kesesuaian dengan Sasaran Pembangunan Lestari (SDG) Pertubuhan Bangsa-Bangsa Bersatu (PBB). Lembaga Jurutera Malaysia (BEM) memainkan peranan penting dalam memastikan kualiti dan keselamatan dalam bidang kejuruteraan, sejajar dengan SDG 9 yang menekankan pembangunan infrastruktur berdaya tahan, inklusif dan berkelanjutan

A route to a high-impact journal article: The most functional strategy in modern history

This book contains valuable information for readers seeking to make informed decisions. However, it is crucial to seek the advice of professionals (such as legal or financial advisors) before making any decisions based on the content of this book. The book also features information, products or services from third-party sources, and we do not assume responsibility or liability for their accuracy or opinions. Conducting due diligence and independently verifying all information, products and services before making any business decisions are essential.The book also features information, products or services from third-party sources, and we do not assume responsibility or liability for their accuracy or opinions. Conducting due diligence and independently verifying all information, products and services before making any business decisions are essential

Analysis of Correlation of Induced Frequency and Cream Skimming Efficiency through Ultrasonic Technology

Ultrasonic cream separator is a very new technology especially in the dairy industry. Ultrasonic separator machine is an eco-friendly technology that could boost the separation process and it could act as supplement to heat-based technology. However, ultrasonic separators are well developed in other industries such as sludge separation, emulsion breaking, de-oiling and sewage disposal. This technology has been implemented in the food industries recently too. The primary function of an ultrasonic cream separator machine is to separate the milk into two products i.e., cream, and skimmed milk. It is an instantaneous process which saves up workload, manpower, time, and cost. This machine intends to coagulate the fat particles with one another once a certain frequency is induced in the milk. Cream, which is lighter molecule will coagulate and float, whereas the heavier molecules of milk such as protein and minerals will sink. Upon separation, the fat molecules can be scooped out or separated through flushing from below. This machine is at a very agile stage that leads to inefficient cream skimming which leads to fluctuation of fat particles coagulation that leads to inefficient cream skimming. The intention of this study is to evaluate the factors that have a direct relationship with low performance of cream skimming via ultrasonic cream separation and come up with an ideal possible solution to enhance the process of cream separation

Parameter influence on mechanical properties of ABS; using FDM

Additive manufacturing (AM), also known as solid-freeform, fast prototyping, and threedimensional (3D) printing, is one method for creating goods from 3D model data. This cuttingedge technology has the potential to replace many existing production procedures and open up new markets for new products. The AM technology known as fused deposition modelling (FDM) is very popular. The mechanical characteristics of 3D printed goods made by FDM, however, are significantly impacted by a small range of variables. This study examines how the tensile characteristics of ABS printed using different raster angles and infill density affect the final product. Acrylonitrile butadiene styrene (ABS), a thermoplastic substance derived from petroleum, was the material employed in the study's filament. Due to its characteristics, ABS is a great material for a variety of structural applications. This study is to fabricate tensile specimens with various temperatures of 50%,75% and 100% also raster angles of 0°, 45° and 90°. The result shows that maximum ultimate tensile strength (UTS), elasticity, and yield strength were obtained at an infill density of 100% with a raster angle of 90°. Thus, infill percentage and raster angle play an important role in deciding better properties of ABS samples produced using FDM

Investigation of mechanical properties of 3d-printed polylactic acid (PLA)

In recent years, 3D printing has contributed to developing new materials and applications, owing to its technological flexibility and distinct characteristics. Polylactic Acid (PLA) polymer samples have been produced using one of the additive manufacturing (AM) processes called fused deposition modelling (FDM). However, poor mechanical characteristics are the most prevalent problem due to the processing parameter when parts are fabricated with FDM. The research aims to study the tensile properties of PLA by varying the processing parameter. In this study, PLA material was used due to its biocompatibility properties. This research is to analyze and compare the tensile properties of 3D printed samples by varying the infill density and raster angle. The change in the circumstances has a discernible impact on the tensile strength based on varied infill densities and raster angles. The results show that infill density of 100% and 45° raster angle performs better tensile strength than 50% and 75% infill density. Hence, it can be concluded that the tensile strength of the printed samples has a noticeable effect when the processing parameters vary

Fused deposition modeling: process, materials, parameters, properties, and applications

In recent years, 3D printing technology has played an essential role in fabricating customized products at a low cost and faster in numerous industrial sectors. Fused deposition modeling (FDM) is one of the most efficient and economical 3D printing techniques. Various materials have been developed and studied, and their properties, such as mechanical, thermal, and electrical, have been reported. Numerous attempts to improve FDM products’ properties for applications in various sectors have also been reported. Still, their applications are limited due to the materials’ availability and properties compared to traditional fabrication methods. In 3D printing, the process parameters are crucial factors for improving the product's properties and reducing the machining time and cost. Researchers have recently investigated many approaches for expanding the range of materials and optimizing the FDM process parameters to extend the FDM process’s possibility into various industrial sectors. This paper reviews and explains various techniques used in 3D printing and the various polymers and polymer composites used in the FDM process. The list of mechanical investigations carried out for different materials, process parameters, properties, and the FDM process's potential application was discussed. This review is expected to indicate the materials and their optimized parameters to achieve enhanced properties and applications. Also, the article is highly anticipated to provide the research gaps to sustenance future research in the area of FDM technologies

Thermally conductive polymer nanocomposites for filament-based additive manufacturing

Thermal management is a crucial factor affecting the performance and lifetime in several applications, such as electronics, generators, and heat exchangers. Additive manufacturing (AM) techniques provide a new revolution in manufacturing by expanding freedom for design and fabrication for complex geometries. One way to overcome these problems is by developing novel polymer-based composite materials with improved thermal conductivity properties for AM technologies. In this review, the fundamental principles of designing high thermal conductive polymer nanocomposites are presented. High thermal conductive polymer nanocomposites generally consist of the base polymer and thermally conductive filler materials such as aluminum oxide or boron nitride which are reviewed in detail. The factors affecting the thermal conductivity of composites, such as the filler loading and overall composite structure, are also summarized. This article stands on statistical data from technical papers published during 2000–2020 about the topics of fused deposition modeling (FDM) polymers or their thermal conductive composites. Finally, the most critical factors affecting the thermal conductivity of polymer nanocomposites are described in detail. Nonetheless, various novel techniques show the potential abilities of thermal conductivity of polymer nanocomposites usage by AM technologies, enabling applications in LED devices, energy, and electronic packaging. Graphical abstract: [Figure not available: see fulltext.

Heat transfer performance of a radiator with and without louvered strip by using graphene-based nanofluids

The present work is focused on the Graphene-based nanofluids with high thermal conductivity which helps to improve the performance and enhance heat transfer. The thermal systems emphasis on the fluid coolant selection and statistical model. Graphene is a super-material, lighter than air, high thermal conductivity, and chemical stability. The purpose of the research is to work up with Graphene-based Nanofluids i.e., Graphene (G) and Graphene oxide (GO). Nanoparticles are dispersed in a base fluid with a 60:40 ratio Water & Ethylene Glycol and at different volume concentrations ranging from 0.01%-0.09%. Radiator model is designed in modelling software and louvered strip is inserted. The simulation (Finite Element Analysis) is performed to evaluate variation in temperature drop, enthalpy, entropy, heat transfer coefficient and total heat transfer rate of the considered nanofluids, results were compared by with and without louvered strip in the radiator for the temperature absorption. 58-60% enhancement of enthalpy observed when Graphene and Graphene oxide nanofluid was utilized. 1.8% enhancement of entropy is observed in 0.09% volume concentration of the Graphene and Graphene oxide nanofluid when louvered strips are inserted in the radiator tube at a flow rate of 3 LPM. With louvered strip inserted in the radiator, heat transfer coefficient enhanced by 236% for Graphene and 320% enhancement is identified for Graphene oxide nanofluid when compared to without louvered strip insert. The results stated that high performance is observed with the utilization of louvered strip in the radiator tube