Showing 3 results for Dissolution
M. Farhani,, M. Soltanieh, M. R. Aboutalebi,
Volume 5, Issue 3 (9-2008)
Abstract
Abstract: Dissolution and recovery of Mn-Al compacts with and without a chloride flux was
studied by taking samples from the melt after addition of the compact. Events occurring after the
addition of the compacts into the melt were studied using water quenched specimens after holding
them for a specified time in molten state. The cross sections of these specimens were characterized
by SEM as well as optical imaging. The results showed that an optimized amount of flux (10 to
15%wt. in this research) considerably decreases the time to reach more than 90% recovery in
comparison with non-fluxed compacts. The flux caused the intermetallic forming reactions to be
started considerably sooner in fluxed compacts in comparison with the non-fluxed compact.
Consequently, the incubation time decreased from about 180 seconds for non-fluxed compacts to
less than 3 seconds for compacts with 10%wt. flux.
A. Shokuhfar, S. Ahmadi, H. Arabi, S. Nouri,
Volume 6, Issue 3 (9-2009)
Abstract
Abstract: Guinier-Preston (GP) zone formation and precipitation behavior of T1 (Al2CuLi) phase during the ageingof an Al-Cu-Li-Zr alloy was studied by differential scanning calorimetry (DSC) technique and electrical resistancemeasurement of the samples. Results show that endothermic effects in the thermograms of the alloy between 180°Cand 240°C can be related to the enthalpy of GPzones dissolution. Formation of GPzones in the structure increasedhardness, tensile strength and electrical resistance of the Al-Cu-Li-Zr alloy. Furthermore, precipitation of T1 phaseoccurred in temperature range of 250ºC to 300ºC whereas its dissolution occurred within the temperature of 450-530ºC. Activation energies for precipitation and dissolution of T1 phase which were determined for the first time inthis research, were 122.1(kJ/mol) and 130.3(kJ/mol) respectively. Results of electrical resistance measurementsshowed that an increase in the aging time resulted in the reduction of electrical resistance of the aged samples.
Hamed Nadimi, Hossein Sarpoolaky, Mansour Soltanieh,
Volume 20, Issue 4 (12-2023)
Abstract
In the present investigation, an attempt was made to evaluate the dissolution behavior of Ti in molten KCl-LiCl. The X-ray diffraction (XRD) pattern of heated Ti plate at 800 oC for 4 h without carbon black in molten salt revealed that TiCl3 formation was feasible. For more assurance, Ti plate was heated at 950 oC for 4 h in the presence of carbon black to identify synthesized TiC. Transmission electron microscope (TEM) and scanning electron microscope (SEM) images from precursors and the final product showed that nano-crystalline TiC formation from coarse Ti particles was almost impossible without Ti dissolution. Thermodynamics calculations using Factsage software proved that it was possible to form various TiClx compounds. The TiC formation mechanism can be discussed in two possible ways: a reaction between Ti ion and carbon black for synthesizing TiC (direct) and a reaction between TiCl4 and carbon black led to indirect TiC synthesis. Elemental mapping using energy dispersive X-ray spectroscope (EDS) indicated that up to 815 oC, chlorine existed in the map.
