Corrosion Behavior of Inconel 625 Coating Produced by Laser Cladding

Anti-corrosion properties of Inconel 625 (In) laser cladding coatings onto the (S235JR) steel (S) were investigated. The coatings were produced with the use of wire (WIn/S) or powder (PIn/S). The mechanical properties of the Inconel 625 coatings were characterized by microhardness measurements. The PIn/S shows the highest hardness. The surface and microstructure of the specimens were observed by a scanning electron microscope (SEM). The surface analysis of the laser cladding coatings by energy-dispersive spectroscope (EDS) indicated that the structure of the WIn, and PIn coatings depend on its production technique. The microstructure of the WIn and PIn coatings have a dendritic columnar character. Corrosion test materials were carried out by using electrochemical methods. The corrosive environment was acidic chloride solution. It turned out that the PIn/S coating, which was produced by laser cladding method with the use of Inconel 625 powder, has the best anti-corrosion properties in an aggressive chloride environment.

Synthesis and Characterization of In-Situ AA8011-TiB2 Composites Produced by Flux Assisted Synthesis

In-situ aluminium alloy 8011 matrix composites containing different weight percentages of titanium diboride were synthesized by flux assisted synthesis using stir casting technique. The metallurgy of the in-situ AA8011-TiB2 composites was analyzed using X-ray diffractometer, scanning electron microscope and energy dispersive spectroscope to disseminate the formation and distribution of reinforcements. Density, microhardness and tensile strength of cast AA8011 and in-situ AA8011-TiB2 composites were measured and analyzed. The in-situ formed TiB2 reinforcements showed the maximum hardness of 55.03 Hv and the maximum tensile strength of 158.2 MPa for 8 wt. % of TiB2 whereas the percentage elongation of 7.2% is observed at 4 wt. % of TiB2. Further, the fractography analysis performed on the fractured tensile samples and the mechanism of failures were identified and reported.

Effect of Ultraviolet Exposure to the Cylindrica (L.) Beauv. Fiber Characteristics

This article explains usage of the ultraviolet irradiation method on Beauv cylindrical (L) imperata fibers as a new way of natural fiber treatment, based on the absorption of ultraviolet rays containing other elements that lead to lignin degradation, which enhances natural fiber strength. Using the ultraviolet exposed fiber method with intervals of 10, 20, 50, and 100 hours, each treatment was tested with scanning electron microscope-energy dispersive spectroscope. The authors found that the treatment resulted in an increase in the fiber’s tensile strength. The results of fiber treatment with 50-hour irradiation produced a fiber with a tensile strength of 130.2 MPa. Our method allows an increase in the AL2O3 element, which indicates an increase in fiber tensile strength of 130.2 Pa. An evaluation of the effectiveness of the new method can be seen in the scanning electron microscope-energy dispersive spectroscope test results. The Imperata Cylindrica (L) Beauv fiber surface roughness test results showed an increase in surface roughness to 1.47 μm resulting from the 50-hour ultraviolet treatment. With this roughness, the adhesion between the fiber and epoxy resin increases. This increased fiber tensile strength and surface roughness, as a result of ultraviolet light treatment, offers the potential for its use as a composite reinforcement.

Synthesis of Cuprous Oxide Nano Cubes and Platelets Using Both Electrodes of Copper

Cu2O (Cuprous Oxide) is usually produced using expensive electrodes such as platinum, graphite, etc. In the present study, it is shown that Cu2O nanostructures can be synthesized by electrolysis using copper as both anode and cathode. In the present study, the effect of electrolyte pH on the morphology of the Cu2O nanostructures was studied. For this, the copper electrodes of 99.99% purity with 3x3x0.3 mm dimensions were dipped in the electrolytes of simple distilled and double distilled water and connected with the external power source. The synthesized products were analyzed using SEM (Scanning Electron Microscope), EDS (Energy Dispersive Spectroscope) and UV spectroscope. Results showed that Cu2O nanostructures of 67 and 150 nm size were developed when the pH of electrolyte was 6.4 and 5.7 respectively, otherwise not. From the course of experiments conducted in this work it is noted that pH play vital role in the production of Cu2O nanoparticles using simple electrolysis technique.

Evaluation of Mesh of Liberation of Zard Koh and Kulli Koh Iron Ores of Pakistan

Liberation size plays a significant role to select a correct and successful concentration method for natural iron ores. This paper aims to evaluate the liberation size of two newly discovered iron ores, namely Zard Koh and Kulli Koh, existing in Chagai region of Pakistan. Zard Koh iron ore is mainly composed of maghemite along with the pyrite, chlorite, grossular and admontite as gangue minerals, whereas, Kulli Koh iron ore is comprised of hematite mostly with quartz, dravite and kaolinite as the gangue minerals. The representative samples of ores were pulverized and sieved to different size fractions. The liberation size of iron bearing minerals and gangues was investigated by analyzing the different size fractions of each ore using XRF (X-Ray Fluorescence), SEM (Scanning Electron Microscope) attached with EDS (Energy Dispersive Spectroscope). The XRF results revealed that the most probable liberation size of Zard Koh and Kulli Koh ores is most likely existing at -75+45 and -150+106 m, respectively. In order to confirm this liberation size, further evidences were collected using SEM and EDS examinations. It is interesting to note that the results obtained from SEM and EDS were quite in agreement with XRF results.

PIN DIAMETER EFFECT ON MICROSTRUCTURE AND MECHANICAL PROPERTIES OF DISSIMILAR FRICTION STIR LAP WELDING ALUMINUM ALLOY 6061-T6 TO DUAL PHASE STEEL

<p class="AMSmaintext"> </p><p class="AMSmaintitle">Abstract</p><p class="AMSmaintext">In this work, the effect of the pin diameter on the microstructure, hardness and strength of friction stir welded 6061-T6 aluminum alloy to dual phase steel have been investigated. Microhardness measurements, tensile shear tests, optical microscopy, and scanning electron microscopy with energy dispersive spectroscope (EDS) were the main techniques used. The results showed that friction stir welding can be used for the joining of dissimilar 6061-T6 aluminum alloy to dual phase steel. We have found that the maximum strength is obtained after welding with the highest pin diameter. </p>

Effect of Carbon Nanotubes on Properties of Ceramics Based Composite Coatings

In the present work, 2% and 6% carbon nanotubes (CNT) were reinforced in chromium oxide powder and were deposited on T22 steel using high velocity oxy-fuel spraying process. The effect of CNT reinforcement on hardness and porosity was investigated. The hardness was observed to be highest for coating reinforced with 6%CNT and hardness was found to increase with decrease in porosity. The coating microstructure and elements were characterised using field emission scanning electron microscopy (FE-SEM) with energy dispersive spectroscope (EDS), Elemental point analysis and X-ray mapping analysis. The constituents of the coating were identified using X-ray diffractometer. It was found that the CNT were uniformly distributed throughout Cr2O3matrix. The CNT were found to be chemically inert during the spraying process.

Macro-microscopic research in reideer (Rangifer tarandus) hoof suitable for efficient locomotion on complex grounds

Introduction: Reindeer are adapted to long distance migration. This species can cope with variations in substrate, especially in ice and snow environment. However, few detailed studies about reindeer hoof are available. Thus this article describes the results of studies on macro- and micro-structures of reindeer hoof.Material and Methods: The gross anatomy of the reindeer hooves was examined. Stereo microscope (SM) and a scanning electron microscope (SEM) were used to observe four key selected positions of reindeer hooves. Moreover, element contents of the three selected positions of reindeer hooves were analysed using the SEM equipped with energy dispersive spectroscope.Results: Hoof bone structures were similar to other artiodactyl animals. In the microscopic analysis, the surfaces of the ungula sphere and ungula sole presented irregular laminated structure. Ungula edge surfaces were smooth and ungula cusp surfaces had unique features. Aside from C, O, and N, reindeer hooves contained such elements as S, Si, Fe, Al, and Ca. The content of the elements in different parts varied. Ti was the particular element in the ungula sole, and ungula edge lacked Mg and S which other parts contained.Conclusion: The macro- and micro-structures of the reindeer hooves showed high performance of skid and abrasion resistance. It is most probably essential to the long distance migration for the animals.

Efficient removal of Cd2+ ion from water by calcium alginate hydrogel filtration membrane

Calcium alginate (CaAlg) hydrogel filtration membrane was prepared using urea as pore-forming agent. The effects of preparation and operating conditions on the removal rate of Cd2+ were researched. The removal mechanism of Cd2+ and the anti-fouling property of CaAlg membrane were investigated. The removal rate of the CaAlg filtration membrane reached over 99.5% within 120 min when 20 mg/L Cd2+ was used, and the flux was 15.5 L/m2h at 0.1 MPa when the thickness of the membrane was 0.28 ± 0.08 mm. However, the removal rate of Cd2+ was below 10.0% when the same concentration Cd2+ solution was adsorbed by CaAlg membrane with the same size. Energy dispersive spectroscope analysis demonstrated that the removal of Cd2+ depended on the adsorption and ion exchange of Ca2+ by Cd2+. CaAlg membrane exhibited a higher removal rate for Cd2+ (almost 100%). It was the filtration process that promoted the adsorption and ion exchange of Cd2+ in CaAlg hydrogel.

Microstructural Transformation of Titanium-Boron Carbide (B4C) Powder Mixture during Spark Plasma Sintering

Present study investigates the microstructural evolution and in-situ formation of Ti/(TiB+TiC) composite. The sintered compacts are having near theoretical density. The relative density of Ti/(TiB+TiC) composites decreases with increasing TiB and TiC content.The phase evolutions of TiB and TiC according to the in-situ reactions are analyzed by X-Ray diffraction technique (XRD). Optical microscope (OM) and Energy dispersive spectroscope (EDS) observations of the Ti/(TiB+TiC) composites shows the presence of TiC and TiB reinforcements as equiaxed and needle like structures respectively.