Preparation of TiB2-20 Wt Pct MoSi2 Composite Material by Mechanochemical Synthesis and Spark Plasma Sintering

Metallurgical and Materials Transactions A - The mechanosynthesis process of composite powders for the preparation of a TiB2-20 wt pct MoSi2 composite material from...     

Microstructure and Magnetic Properties of 6.5 Wt Pct Si Steel Strip Produced by Simulated Strip Casting Process

Metallurgical and Materials Transactions A - An improved dip test apparatus was used to simulate the strip casting of 6.5 wt pct Si steel in this study. The results showed that the...     

A Coupled Small and Wide-Angle X-Ray Scattering Study of Phase Transformation Mechanisms in U-6Wt Pct Nb

Metallurgical and Materials Transactions A - The elevated temperature phase transformation kinetics of U-6wt pct Nb in both wrought and cast conditions were investigated using in-situ...     

Effects of CaO/SiO2 Ratio and Na2O Content on Melting Properties and Viscosity of SiO2-CaO-Al2O3-B2O3-Na2O Mold Fluxes

Metallurgical and Materials Transactions B - This paper investigated the effects of CaO/SiO2 ratio (0.8 to 1.5) and Na2O concentration (6 to 9 wt pct) on melting properties and viscosity...     

Structural Characterization of Binary Al-Cu Alloy Processed by Equal Channel Angular Pressing at Half of the Melting Point

Metallurgical and Materials Transactions A - Microstructure evolution in Al-3 wt pct Cu alloy during equal-channel angular pressing (ECAP) at 423 K (150 °C)...     

Investigation on Al6Fe Fibers of Al-3 Wt Pct Fe Alloy at Different Mold Temperatures

Metallurgical and Materials Transactions B - Al-3Fe alloys with nearly full Al6Fe fibers are obtained via iron mold casting at different mold temperatures (293 K, 323 K,...     

Hot Oxidation Resistance of a Novel Cast Iron Modified by Nb and Al Addition for Exhaust Manifold Applications

Metallurgical and Materials Transactions A - In this study, high-temperature oxidation behavior of ductile cast irons designed by Nb and Al addition (3.5 wt pct C, 4 wt pct Si, 1...     

Further Insight into Interfacial Interactions in Iron/Liquid Zn-Al System

Metallurgical and Materials Transactions A - In the galvannealing process, steel strips are immersed in molten zinc containing 0.100 to 0.135 wt pct Al at 450 °C....     

Experimental Study on the Activities of Al and Ca in Ferrosilicon

Metallurgical and Materials Transactions B - Experiments were carried out to determine the activities of Al and Ca in liquid ferrosilicon (with about 50 wt pct Si) at...     

Role of Mechanical Stirring of Al-Mg Melt in the Healing of Bifilm Defect

Metallurgical and Materials Transactions B - The effect of mechanical stirring of aluminum melts containing 0.3, 0.7, and 4.5 wt pct Mg with a graphite rotor with different...     

Wear Behavior of the Lead-Free Tin Bronze Matrix Composite Reinforced by Carbon Nanotubes

Copper-coated carbon nanotubes were prepared by the electroless plating route. The structure and component of copper/carbon tubes were characterized using a transmission electron microscope and energy dispersive spectrometer. The results show that the surface of the carbon tubes was covered by the copper particles. Copper/carbon tubes were used as the substitute of part of tin and all of lead in the tin bronze matrix, and the tribological properties of carbon nanotube-reinforced Cu-4 wt pct Sn-6 wt pct Zn composites were studied. The effects of the carbon nanotube volume fraction and sliding distance in unlubricated ball-on-disc wear test were investigated. The 3 vol pct carbon nanotube-reinforced Cu-4 wt pct Sn-6 wt pct Zn composite shows the Vickers hardness of 126.9, which is approximately 1.6 times higher than that of Cu-6 wt pct Sn-6 wt pct Zn-3 wt pct Pb tin bronze. The wear rate and average friction coefficients of 3 vol pct carbon nanotube-reinforced Cu-4 wt pct Sn-6 wt pct Zn composite were lower than those of the Cu-6 wt pct Sn-6 wt pct Zn-3 wt pct Pb tin bronze, respectively.     

Confocal Scanning Laser Microscopy Studies of Crystal Growth During Oxidation of a Liquid FeO-CaO-SiO<Subscript>2</Subscript> Slag

The oxidation of FeO in 30 wt pct FeO-35 wt pct CaO-35 wt pct SiO₂ slag was investigated as part of a wider study on the recovery of Fe units through magnetic separation. A confocal scanning laser microscopy (CSLM) technique was used to visualize the oxidation of FeO in the liquid slag. The formation event was observed in situ under the CSLM and the onset of precipitation on a surface of the slag liquid was recorded at various temperatures in an oxidizing atmosphere. A Time-Temperature-Transformation (TTT) diagram was constructed based on the CSLM results. Samples obtained from the CSLM heating chamber were analyzed by a scanning electron microscope (SEM) equipped with an energy-dispersive spectrometer (EDS).     

Effect of Cryogenic Thermal Cycling on Tribocorrosion Performance of Fe-Based Bulk Amorphous Alloy in 3.5 Pct NaCl Solution

Metallurgical and Materials Transactions A - The effects of cryogenic thermal cycling on the tribocorrosion behavior of Fe41Co7Cr15Mo14C15B6Y2 bulk amorphous alloy were studied in 3.5&nbsp;pct...     

Comprehensive Analysis of Microalloying Element V Improving Hydrogen Embrittlement Resistance of 1300MPa Bolt Steel

Metallurgical and Materials Transactions A - In this study, the effect of vanadium addition (0.14&nbsp;wt&nbsp;pct) on microstructure and hydrogen embrittlement (HE) susceptibility were...     

Investigation of the Effects of Ni, Fe, and Mn on the Formation of Complex Intermetallic Compounds in Al-Si-Cu-Mg-Ni Alloys

The aim of this work is to partially substitute Fe and Mn for Ni in the 3HA piston alloy and to study the consequences through microstructural evaluation and the thermal analysis technique. Three types of near-eutectic alloys containing (2.6 wt pct Ni-0.2 wt pct Fe-0.1 wt pct Mn), (1.8 wt pct Ni-0.75 wt pct Fe-0.3 wt pct Mn), and (1 wt pct Ni-1.15 wt pct Fe-0.6 wt pct Mn) were produced, and their solidification was studied at the cooling rate of 0.9 K/s (°C/s) using the computer-aided thermal analysis technique. Optical microscopy and scanning electron microscopy were used to study the microstructure of the samples, and energy dispersive X-ray (EDX) analysis was used to identify the composition of the phases. Also, the quantity of the phases was measured using the image analysis technique. The results show that Ni mainly participates as Al₃Ni, Al₉FeNi, and Al₃CuNi phases in the high Ni-containing alloy (2.6 wt pct Ni). In addition, substitution of Ni by Fe and Mn makes Al₉FeNi the only Ni-rich phase, and Al₁₂(Fe,Mn)₃Si₂ appears as an important Fe-rich intermetallic compound in the alloys with the higher Fe and Mn contents.     

Influence of CaF<Subscript>2</Subscript> and Li<Subscript>2</Subscript>O on the Viscous Behavior of Calcium Silicate Melts Containing 12 wt pct Na<Subscript>2</Subscript>O

Understanding the viscous behavior of silica-based molten fluxes is essential in maintaining the reliability of steel casting operations and in preventing breakouts. In particular, high concentrations of aluminum in recently developed transformation induced plasticity (TRIP) and twinning induced plasticity (TWIP) steels tend to promote reduction of silica in the mold fluxes that result in the formation of alumina, which in turn increases the viscosity. To counteract this effect, significant amounts of fluidizers such as CaF₂ and Li₂O are required to ensure that mold fluxes have acceptable lubrication and heat transfer characteristics. The viscous behavior of the slag system based on CaO-SiO₂-12 wt pct Na₂O with various concentrations of CaF₂ and Li₂O has been studied using the rotating spindle method to understand the effects on the viscosity with these additives. CaF₂ additions up to 8 wt pct were effective in decreasing the viscosity by breaking the network structure of molten fluxes, but CaF₂ concentrations above this level had a negligible effect on viscosity. Li₂O additions up to 2 wt pct were also effective in decreasing the viscosity, but the effect was comparatively negligible above 2 wt pct. Using Fourier transform infrared (FTIR) analysis of as-quenched slag samples, it was concluded that the viscosity was controlled more effectively by changing the larger complex silicate structures of rings and chains than by changing the amounts of simpler dimers and monomers.     

Evolution of Texture,Grain Boundary Constitution,Strain, and Corrosion Behavior of Electrodeposited Ni–P Coatings as a Function of Deposition Current Density

Metallurgical and Materials Transactions A - Ni–P coatings with low P content (P wt&nbsp;pct &lt; 1.0) were fabricated at different applied current densities of electrodeposition...     

Thermal Stability in Nanocrystalline Fe-30?Wt?Pct Ni Alloy Induced by Surface Mechanical Attrition Treatment

By means of surface mechanical attrition treatment (SMAT), a nanocrystalline surface layer is produced in Fe-30 wt pct Ni alloy, accompanying the formation of the strain-induced martensite. The thermal stability of nanocrystalline martensite and parent phase austenite in Fe-30 wt pct Ni alloy is studied by X-ray diffraction (XRD) and transmission electron microscope (TEM). The grain growth kinetics parameters, time exponent, n, and activation energy, Q, for both martensite and austenite, are determined, respectively. The TEM observations indicate that abnormal grain growth occurs during annealing at high temperatures.     

Thermodynamics of Arsenic in FeOx-CaO-SiO<Subscript>2</Subscript> Slags

The distribution of arsenic between calcium ferrite slag and liquid silver (wt pct As in slag/ wt pct As in liquid silver) with 22 wt pct CaO and between iron silicate slag with 24 wt pct SiO₂ and calcium iron silicate slags was measured at 1573 K (1300 °C) under a controlled CO-CO₂-Ar atmosphere. For the calcium ferrite slags, a broad range of oxygen partial pressure (10^–11 to 0.21 atm) was covered, whereas for the silicate slags, the oxygen partial pressure was varied from 10^–9 to 3.1 × 10^–7 atm. The measured relations between the distribution ratio of As and the oxygen partial pressure indicates that the oxidation state of arsenic in these slags is predominantly As³⁺ or AsO_1.5. The measured distribution ratio of arsenic between the calcium ferrite slag and the liquid silver was about an order of magnitude higher than that of the iron silicate slag. In addition, an increasing concentration of SiO₂ in the calcium-ferrite-based melts resulted in decreases in the distribution of arsenic into the slag. Through the use of measured equilibrium data on the arsenic content of the metal and slag in conjunction with the composition dependent on the activity of arsenic in the metal, the activity of AsO_1.5 in the slags was deduced. These activity data on AsO_1.5 show a negative deviation from the ideal behavior in these slags.     

Kinetics of κ Discontinuous Precipitation in Co-10Al-3Cu-1C (At. Pct)

Metallurgical and Materials Transactions A - Electron microscopy revealed continuous and discontinuous precipitation of κ-Co3AlC0.5 in a Co-10Al-3Cu-1C (at.&nbsp;pct) alloy during aging at...