Recently added articles from Metallurgical and Materials Transactions:
Clays, Nanoclays, and Montmorillonite Minerals
Dec 01, 2008; ... The recent introduction of nanoclays as fillers or additives in polymers for various desired effects is a subject of an increased interest for research and development to establish various applications. An increased consumption is indicated by the wider applications of clay nanocomposites ...
Analytical Electron Microscopy Study of Boron-Rich Grain Boundary Microconstituent in Directionally Solidified RENE 80 Superalloy
Dec 01, 2008; ... Analytical transmission electron microscopy study of intergranular regions in directionally solidified (DS) RENE 80 superalloy was performed. In addition to the generally reported M^sub 3^B^sub 2^-type boride particles that form in the alloy during ingot solidification, considerable presence of ...
Selective Oxidation of a CMnSi Steel during Heating to 1000 °C: Reversible SiO^sub 2^ Oxidation
Dec 01, 2008; ... Many multiphase cold-rolled high-strength steels require complex thermal processing, including a (partial) austenitization to reach the desired microstructure. However, of importance for their galvanizability, the selective oxidation of these steels in the austenitic region has not been studied ...
Microstructural Influences on Very-High-Cycle Fatigue-Crack Initiation in Ti-6246
Dec 01, 2008; ... The fatigue behavior of an alpha + beta titanium alloy. Ti-6Al-2Sn-4Zr-6Mo, has been characterized in the very-high-cycle fatigue (VHCF) regime using ultrasonic-fatigue (20 kHz) techniques. Stress levels (σ^sub max^) of 40 to 60 pct of the yield strength of this alloy have been examined ....
Residual Stresses in Friction-Stir-Welded 2195 and 7075 Aluminum Alloys
Dec 01, 2008; ... Surface residual stresses (RSs) were characterized along friction-stir-welded 2195 and 7075 aluminum alloy (AA) plates. The surface measurements were obtained through X-ray diffraction (XRD) at five different locations along the weld. Each location consisted of several regions across the welded ...
Dependency of Recrystallization Mechanism to the Initial Grain Size
Dec 01, 2008; ... The effect of initial grain size on the recrystallization behavior of a type 304 austenitic stainless steel during and following hot deformation was investigated using hot torsion. The refinement of the initial grain size to 8 µm, compared with an initial grain size of 35 µm, had considerable ...
Size Effect of Rare-Earth Intermetallics in Sn-9Zn-0.5Ce and Sn-3Ag-0.5Cu-0.5Ce Solders on the Growth of Tin Whiskers
Dec 01, 2008; ... In contrast to the large cluster-shaped CeSn^sub 3^ peritectic phase formed in Sn-3Ag-0.5Cu-0.5Ce solder, Sn-9Zn-0.5Ce possesses very fine (Ce^sub 0,8^Zn^sub 0,2^)Sn^sub 3^ intermetallics. Image analyses indicate that the total exposed area of fine peritectic intermetallics in Sn-9Zn-0.5Ce ...
In-Situ Transmission Electron Microscopy Observation on the Phase Transformation of Ti-Nb-Sn Shape Memory Alloys
Dec 01, 2008; ... The microstructural changes accompanied by phase transformation during heating and cooling of quenched (Ti-35 wt pet Nb)-O to 6 wt pet Sn alloys have been investigated using in-situ transmission electron microscopy (TEM). Reversible transformation between orthorhombic oc" and body-centered-cubic ...
Effects of Applied Load on 6061-T6 Aluminum Joined Employing a Novel Friction Bonding Process
Dec 01, 2008; ... Friction bonding is under consideration for use in mass production of plate-type nuclear fuels for research reactors. This article discusses the effects of applied load (the most important process parameter for fabrication of these fuels) on temperature distribution, microstructure, and ...
Mechanical Blocking Mechanism for the Columnar to Equiaxed Transition
Dec 01, 2008; ... Mechanical blocking of the columnar front during the columnar to equiaxed transition (CET) is studied by quantitatively comparing the CET positions obtained with one stochastic model and two deterministic models for the unidirectional solidification of an Al-7 (wt pct) Si alloy. One of the ...
Effect of Process Parameters, Casting Thickness, and Alloys on the Interfacial Heat-Transfer Coefficient in the High-Pressure Die-Casting Process
Dec 01, 2008; ... The heat transfer at the metal-die interface is believed to have great influence on the solidification process and cast structure of the high-pressure die-casting (HPDC) process. The present article focused on the effects of process parameters, casting thickness, and alloys on the metal-die ...
Microstructural Transitions in Commercial Fe-Ni-Based Soft-Magnetic Alloys Quenched from Undercooled Liquid Droplets
Dec 01, 2008; ... Liquid droplets of three commercial Fe-Ni-based alloys were undercooled to different temperatures by electromagnetic levitation and quenched. Discontinuous changes in the grain size and microstructure as a function of melt undercooling (ΔT) were observed in all three alloys. At ΔT ...
Fabrication of Ti-6Al-4V Scaffolds by Direct Metal Deposition
Dec 01, 2008; ... Direct metal deposition (DMD) is a rapid laser-aided deposition method that can be used to manufacture near-net-shape components from their computer aided design (CAD) files. The method can be used to produce fully dense or porous metallic parts. The Ti-6Al-4V alloy is widely used as an ...
Optimization of the Machinability of the Al-SiC Metal Matrix Composite Using the Dynamic Material Model
Dec 01, 2008; ... The dynamic material model (DMM) method has been widely used for the macroscopic description of flow, fracture, and workability of materials under hot deformation. This investigation is aimed at proposing a new methodology for the optimization of hot machinability of a material using the DMM ...
Microstructure of ECAE-Processed Copper after Long-Term Room-Temperature Storage
Dec 01, 2008; ... The microstructure in two copper samples processed by equal channel angular extrusion (ECAE) using either 90 deg rotations between passes (route Bc) or without rotations (route A) has been examined following storage at room temperature for a period of 8 years. In both samples the deformation ...
Low-Temperature Coarsening and Plastic Flow Behavior of an Alpha/Beta Titanium Billet Material with an Ultrafine Microstructure
Dec 01, 2008; ... The influence of microstructure evolution on the low-temperature superplasticity of ultrafine alpha/beta titanium alloys was established. For this purpose, the static and dynamic coarsening response and plastic flow behavior of Ti-6A1-4V with a submicrocrystalline microstructure were determined ...
Recrystallization during Thermomechanical Processing of IMI834
Dec 01, 2008; ... The microstructure development of the near-a titanium alloy IMI834 displaying an initial bimodal a + ß microstructure has been characterized with respect to dynamic and static ß recrystallization, through quantitative metallography. The investigation was supplemented by interrupted compression ...
Effect of Variation in Process Parameters on the Formation of Freckle in INCONEL 718 by Vacuum Arc Remelting
Dec 01, 2008; ... In order to study the effect of variation in process parameters on the final ingot of INCONEL 718 during vacuum arc remelting, a 508-mm-diameter vacuum arc remelting (VAR) ingot of INCONEL 718 was produced under conditions of variation in electrode diameter and arc gap. It was sectioned and ...
Ti (Zr)-Cu-Ni Bulk Metallic Glasses with Optimal Glass-Forming Ability and Their Compressive Properties
Dec 01, 2008; ... The formation of bulk metallic glasses (BMGs) was systematically investigated in the ternary Ti-Cu-Ni and quaternary Ti-Zr-Cu-Ni systems. Over a relatively wide composition range (50 to 57 at. pet Ti, 34 to 44 at. pet Cu, and 6 to 10 at. pet Ni) in the ternary Ti-Cu-Ni system, new Ti-based BMGs ...
Understanding Influence of MoSi^sub 2^ Addition (5 Weight Percent) on Tribological Properties of TiB^sub 2^
Dec 01, 2008; ... In densifying engineering ceramics such as TiB^sub 2^ using nonmetallic sinter additives, it is important to assess the influence of the addition of sinter-aid on the properties of TiB^sub 2^. The present article reports how a small addition of MoSi^sub 2^ (5 wt pct) sinter-aid enhances the wear ...