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Microstructure

Journal of Metals, Materials and Minerals

Articles 1 - 9 of 9

Full-Text Articles in Engineering

Dolomite Stabilized Zirconia For Refractory Application : Part-I Phase Analysis, Densification Behavior And Microstructure Of Partial Stabilized Zirconia, R Prasad Rana, P Kumar, A Suvrajit Bal Dec 2013

Dolomite Stabilized Zirconia For Refractory Application : Part-I Phase Analysis, Densification Behavior And Microstructure Of Partial Stabilized Zirconia, R Prasad Rana, P Kumar, A Suvrajit Bal

Journal of Metals, Materials and Minerals

In the continuous casting of steel, Zircon and Zirconia based products are used due to its high thermal stability, excellent erosion resistance, self-opening, consistent casting speed and resistance to oxygen lancing during casting for removal of inclusion clogging and to streamline the flow. Higher casting sequences of molten steel CaO or MgO stabilized zirconia nozzles were being used and for industrial application point of view, dolomite stabilized zirconia (DSZ) could be a better substitute for the stabilization of zirconia. DSZ samples were prepared having 3,4,5,6 and 7 mole % of dolomite by solid state route using high purity monoclinic zirconia …


Influence Of Casting Techniques On Hardness, Tarnish Behavior And Microstructure Of Ag-Cu-Zn-Si Sterling Silver Jewelry Alloys, C. Chanmuang, W. Kongmuang, J.T.H. Pearce, T. Chairuangsri Dec 2012

Influence Of Casting Techniques On Hardness, Tarnish Behavior And Microstructure Of Ag-Cu-Zn-Si Sterling Silver Jewelry Alloys, C. Chanmuang, W. Kongmuang, J.T.H. Pearce, T. Chairuangsri

Journal of Metals, Materials and Minerals

The effects of Zn and Si on the hardness, tarnish resistance and microstructures of experimental Ag-Cu-Zn-Si alloy were investigated by means of vickers hardness, tarnish testing, optical and scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The various compositions of 935 sterling silver alloys produced by different casting techniques, investment (lost wax) process and metal mould casting, were compared. An induction casting machine with a vacuum system was used for investment casting at 1,025C with the mould temperature at 600C whereas a LPG/oxygen single flame tip torch was used for the metal mould process. Vickers hardness of the samples …


A Micromechanical Flow Curve Model For Dual Phase Steels, S. Sodjit, V. Uthaisangsuk Jul 2012

A Micromechanical Flow Curve Model For Dual Phase Steels, S. Sodjit, V. Uthaisangsuk

Journal of Metals, Materials and Minerals

In the automotive industries, Dual Phase (DP) steels have become a favoured material for the car body parts due to their excellent combination of high strength and good formability. A microstructure of DP steel generally consists of a matrix of ferrite reinforced by small islands of martensite. Experimental investigations showed that effects of martensite phase fraction, morphology, and phase distribution play an important role for the mechanical and fracture behaviours of the dual phase steel. In the present work, an approach concerning FE based modelling for predicting flow curve of DP steels has been introduced using a Representative Volume Element …


Development Of An Aluminum Semi-Solid Extrusion Process, T Rattanochaikul, S Janudom, N Memongkol, J Wannasin Dec 2010

Development Of An Aluminum Semi-Solid Extrusion Process, T Rattanochaikul, S Janudom, N Memongkol, J Wannasin

Journal of Metals, Materials and Minerals

Semi-solid extrusion process is a new forming process that is quite promising because the process requires lower forming pressure than conventional solid extrusion. In addition, semi-solid extrusion does not require large machines, which results in lower production costs. The aim of this article is to study the feasibility of an aluminum semi-solid extrusion process. The semi-solid technique selected for usage in this study was the Gas Induced Semi-Solid (GISS) process. The laboratory extrusion system was developed in this work. In the experiments, nitrogen gas was injected into aluminum melt for about 5 seconds. After that, the obtained semi-solid slurry was …


An Investigation Of Microstructural Change Of Low Alloy Steel Aisi 4150 By Seebeck Coefficient, T Samran, P Termsuksawad Jul 2010

An Investigation Of Microstructural Change Of Low Alloy Steel Aisi 4150 By Seebeck Coefficient, T Samran, P Termsuksawad

Journal of Metals, Materials and Minerals

Low alloyed steels, whose hardness can be modified by heat treatment, have been widely used in various applications. After heat treatment, they are normally destructively characterized and tested by many approaches via optical microscope and hardness testing. It is useful to develop a non-destructive method relating to its properties and microstructures. The proposed non-destructive approach in this study is the Seebeck coefficient measurement. The materials in this study were carbon steels AISI 4150 rod with a diameter of 1.3 cm and length of 3 cm. The specimens were heat-treated at 900ºC for 1 hour and were then cooled to room …


Effects Of Yttria Concentration And Microstructure On Electric Breakdown Of Yttria Stabilized Zirconia, O Jongprateep, V Petrovsky, F Dogan Jul 2008

Effects Of Yttria Concentration And Microstructure On Electric Breakdown Of Yttria Stabilized Zirconia, O Jongprateep, V Petrovsky, F Dogan

Journal of Metals, Materials and Minerals

Ceramic materials have great potentials for capacitor application. However, low breakdown strength of the materials remains a key challenge for development of high performance capacitors. In this study, yttria stabilized zirconia (YSZ) were fabricated and tested for breakdown strength. YSZ samples with 3, 8, and 10 mol% yttria were carefully processed to control grain size and porosity level. Experimental results revealed that breakdown strength as high as 2 MV/cm could be achieved. The breakdown strength was not significantly affected by porosity level, but it was by yttria concentration. Relationship among yttria concentration, residual porosity and breakdown strength is discussed in …


Microstructure And Mechanical Properties Of En Aw 6082 Aluminium Alloy Prepared By Equal-Channel Angular Pressing, M Fujda, T Kvačkaj Dec 2007

Microstructure And Mechanical Properties Of En Aw 6082 Aluminium Alloy Prepared By Equal-Channel Angular Pressing, M Fujda, T Kvačkaj

Journal of Metals, Materials and Minerals

The mechanical properties and microstructure of EN AW 6082 aluminium alloy subjected to severe plastic deformation (SPD) and natural ageing are compared with those of extruded and artificially aged state (initial state) and quenched state of alloy after solution annealing. Quenched state of alloy was deformed at room temperature by equal channel angular pressing (ECAP) following route C up to three passes. Polyedric microstructure of quenched state was considerably changed by SPD. Deformation bands with different amount of deformation were observed in microstructure of ECAPed state, which indicated non-uniform deformation across the cross-section of ECAPed specimen. Ultimate tensile strength (UTS) …


Effect Of Solution Annealing Temperature On Structure And Mechanical Properties Of En Aw 2024 Aluminium Alloy, M Fujda, R Mišičko, L Rusňáková, M Sojko Jul 2007

Effect Of Solution Annealing Temperature On Structure And Mechanical Properties Of En Aw 2024 Aluminium Alloy, M Fujda, R Mišičko, L Rusňáková, M Sojko

Journal of Metals, Materials and Minerals

The effect of solution annealing temperature on the change of microstructural and mechanical properties of EN AW 2024 aluminium alloy was investigated using a metallographic analysis, Vickers hardness measurement and tensile test. An intensive growth of solid solution grains was the result of the increase of solution annealing temperature by the finely dispersed particles dissolved during applied annealing process. The role of these finely dispersed particles was to inhibit the recrystallization process and grain growth of solid solution matrix through its pinning effect on the migrated solid solution grain boundaries. Observed changes of the microstructure involved the strength decline and …


Kinetics Of Carbonisation, Microstructure And Properties Of Al-Al4c3 System Prepared By Mechanical Alloying, M Besterci Jul 2006

Kinetics Of Carbonisation, Microstructure And Properties Of Al-Al4c3 System Prepared By Mechanical Alloying, M Besterci

Journal of Metals, Materials and Minerals

The method of mechanical alloying process is described. Carbon transformation to carbide Al4C3 is characterised within different heat treatment schedules and nine commercial carbon powders are tested. The micromechanism of carbon incorporation into the metallic powder, and the compacting of it are described. The influence of dispersed carbides on mechanical properties is evaluated together with the influence of deformation on microstructure and properties.