Microstructure and Strengthening Mechanisms in an HSLA Steel Subjected to Tempforming

An effect of tempforming on the microstructure, the carbide precipitation, and the strengthening mechanisms of high-strength low-alloyed steel has been analyzed. The quenched steel was subjected to 1 h tempering at a temperature of 873 K, 923 K, or 973 K followed by plate rolling at the same temperature. Tempforming resulted in the formation of an ultrafine grained lamellar-type microstructure with finely dispersed carbides of (Nb,V)C, Fe3C and Cr23C6. A decrease in tempforming temperature resulted in a reduction of the transverse grain size from 950 nm to 350 nm. Correspondingly, the size of Fe3C/Cr23C6 particles decreased from 90 nm to 40 nm while the size of (Nb,V)C particles decreased from 17 nm to 4 nm. Refining the tempformed microstructure with a decrease in thetempforming temperature provided an increase in the yield strength from 690 MPa to 1230 MPa.

Growth and scintillation properties of LiBr/CeBr3 eutectic scintillator for neutron detection

The 6LiBr/CeBr3 eutectic scintillator for thermal neutron detection has been developed due to achieving high 6Li concentration. The eutectics were grown by vertical Bridgman method. Molar ratio of 6Li in 6LiBr/CeBr3 eutectic is 35 %, which is higher than that of commercial neutron scintillators such Ce:LiCaAlF6 and Ce:Cs2LiYCl6. The grown eutectic had lamellar-type eutectic structure extending along the growth direction and optical transparency. The grown eutectics showed an emission peak at 360 and 380 nm ascribed to Ce3+ 4f-5d transition from CeBr3 scintillation phase. The measurements of scintillation performance of the 6LiBr/CeBr3 were performed using x-ray, gamma-ray and neutron irradiation to evaluate its potential as a neutron scintillator.

Efficiency of Microstructure Refinement in Ti-Based Alloys

The influence of various factors on the efficiency of microstructure refinement in two-phase titanium alloys with respect to a well-known Ti-6Al-4V alloy was discussed. The kinetics of microstructure evolution in titanium alloys with a lamellar type α/β microstructure during large plastic deformation depends mainly on temperature and strain rate, type of the initial microstructure, thickness of the α lamellae, path of deformation and chemical composition. Each parameter should be controlled to provide the most efficient microstructure refinement during conventional metalforming methods.

Evaluation of the Aging Effect on the Microstructure of Co-28Cr-6Mo-0.3C Alloy: Experimental Characterization and Computational Thermodynamics

In the current research, we studied the role of the solution treatment and aging on the microstructure of a Co–28Cr–5Mo–0.3C alloy. We used metallographic observations, scanning electron microscopy (SEM), and hardness measurements for the evaluations. We also made a comparison between the phase equilibrium calculated with Thermo-Calc, using TCFE8 and TCNI8 thermodynamic databases and experimental findings. The experimental results showed that the transformation of the metastable FCC phase to the HCP phase during aging was extremely sensitive to the solution treatment prior to aging. The effect of the increase in the solution temperature and time was detectable through promotion of the martensitic transformation during quenching in which HCP1 (straight bands) and HCP2 (lamellar-type constitution) phases had developed. In contrast, a low solution temperature and time caused most of the primary carbides to remain in an undissolved condition in the matrix; therefore, during aging, no sign of the FCC to HCP1 (straight bands) phase transformation could be observed. However, we observed the formation of the HCP2 phase (lamellar-type constitution) at the grain boundaries. In addition, the X-ray diffraction pattern indicated that the sample solution treated at lower temperatures and shorter times had a stronger martensitic transformation during aging compared to the sample solution treated at higher temperatures and longer times. Hardness measurements confirmed the results. Thermodynamical calculations showed that an agreement existed between the experiments and calculations. We also discuss the results from the TCFE8 and TCNI8 databases.

A Case Report on Congenital Ichthyosis - Collodion Baby

Collodion baby describes a highly characteristic clinical entity in newborns encased in a yellowish translucent membrane resembling collodion. In most cases the condition either precedes the development of one of a variety of ichthyoses, the commonest of which are lamellar ichthyosis and non-bullous ichthyosiform erythroderma, or occasionally represents an initial phase of other ichthyoses such as ichthyosis vulgaris. In at least 10% of all cases of collodion baby, the condition is followed by a mild ichthyosis of lamellar type, so mild as to be considered more or less normal, so-called self-healing collodion baby or 'lamellar ichthyosis of the newborn'. In this report, we present a severe form of ichthyosis.Faridpur Med. Coll. J. Jan 2016;11(1): 39-42