Effect Of Magnesium Content Research Articles

Effect of magnesium content on plastic properties and internal defects of 708 alloy ingot

The effect of magnesium content on defect rates and yield in bar billets made of 708 alloy obtained by the electric arc furnace smelting, vacuum arc remelting forging method under the conditions of Stupino Metallurgical Company is determined. The effectiveness of the effect on the properties of the alloy is assessed at constant technological parameters of smelting in electric arc furnace and subsequent vacuum arc remelting using statistical analysis based on 92 industrial melts. The presented statistical results of a wide array of melts made it possible to clarify the required optimal magnesium content in the 708 alloy at the stage of producing it in electric arc furnace. It is established that optimal magnesium content allows to obtain a high yield, as well as minimal defects in internal defects identified using ultrasonic testing.

Co-pyrolysis of biomass with magnesium and phosphorus: effect of magnesium content on phosphate release from biochar-based fertilizers

Co-pyrolysis of biomass with magnesium and phosphorus: effect of magnesium content on phosphate release from biochar-based fertilizers

Modeling the Effect of Magnesium Content on the Electrical Conductivity and Hardness of Technical Aluminum (1050) Alloy

Aluminum alloys use is so profound in many applications such as transportation, construction, energy, defense applications, automotive, aerospace, to name a few. Therefore, investigating the mechanical and electrical properties of the different types for aluminum alloys is vital. The Al–Mg alloy is widely used in the automotive industry because of its optimal properties, for example, corrosion resistance, weldability, and strength-to-weight ratio. This study aims to investigate and model the effect of changing the magnesium percentage content on the hardness and electrical conductivity of Al–Mg alloy with a detailed statistical analysis to validate the results. The microstructure at each Mg percentile content is demonstrated using a scanning electron microscope (SEM) and an optical microscope for validating the Mg content after solidification and tracking the grain size evolutions at different Mg percentiles. Vickers hardness testing is applied for hardness evaluation at each experimental condition. The electrical conductivity is tested using a PCE 20COM electric conductive non-destructive test (NDT). Prediction models are constructed to estimate the hardness and electrical conductivity as a function of Mg percentile by using a nonlinear optimizer. The results indicated that the hardness is significantly increased with increasing the Mg content by three times when comparing 0 Mg wt.% and 5 mg wt.%. In contrast, a 48% reduction in the electrical conductivity is found when Mg wt.% is increased to 5 and a notable decrease in the grain size is observed when the Mg content is increased.

Enhancing the catalytic performance of calcium-based catalyst derived from gypsum waste for renewable light fuel production through a pyrolysis process: A study on the effect of magnesium content

The thermochemical conversion of abundant renewable resources through pyrolytic catalysis cracking (PCC) is one of the most promising technologies for producing green biofuels. In this study, the pyrolysis of palm oil was investigated over a sustainable CaO-based catalyst derived from waste gypsum. PCC was conducted in a continuous packed-bed reactor under atmospheric pressure without purge gas. The effects of Mg doping and reaction temperature were also examined. A wet ball milling process was used to prepare the well-mixed catalysts and to subsequently form a heterojunction structure between the CaO and MgO particles. CaO was synthesized using the Ca(OH)2 derived from the reaction between gypsum and sodium hydroxide. The pyrolytic oil was separated from the crude oil to remove water and other impurities. The pyrolytic oil was then distilled following ASTM D86, and the three separated products were classified as bio-gasoline, bio-kerosene, and bio-diesel. The highest renewable light fuel volume (bio-gasoline and bio-kerosene) of about 75% (74 %wt.) was obtained at a reaction temperature of 525 °C with 10% MgCO3 content. The percent volume of light fuel increased with increasing reaction temperature. Renewable light fuel production over the Mg-doped CaO-based catalyst was related to both the Mg content and reaction temperature.

Effect of magnesium content and growth temperature on structural and optical properties of USCVD-grown MgZnO films

Magnesium zinc oxide (MgxZn1-xO) films (x < 0.4) have been grown by ultrasonic spray chemical vapor deposition on soda-lime glass substrates for different growth temperature and different Mg mole fractions (x). Effects of Mg content in the liquid solution and the effect of growth temperature on optical and structural properties of MgZnO films have been investigated with X-ray diffraction, atomic force microscope, and UV–visible spectrophotometry measurements. The growth temperature has a significant effect on determining the Mg mole fractions of MgZnO films. There is a linear correlation between the measured Mg mole fraction in the resulted grown structures and Mg content in the solution. The peak of (0002) diffraction for the grown samples has been shifted to the higher diffraction angles with increase in Mg content in the liquid solution and has also become stronger. The growth temperature and Mg content in a liquid solution are crucial parameters in the controlling Mg mole fraction of samples.

Characterisation of Inhomogeneous Plastic Deformation of AlMg Sheet Metals During Tensile Tests

The Portrevin-Le-Chatelier (PLC) effect was analysed quantitatively in the selected AlMg alloys with Mg-content between 2,8-4,6%. The propagation and characteristics of PLC bands were detected by digital image correlation (DIC) technique and the parameters of the bands were evaluated from strain distributions of tensile test specimens. In parallel, stress-strain curves were analysed evaluating stress serrations. The numerically defined parameters of changes in stress and strain were used for characterising the PLC effect on the behaviour of different sheet metals. General statements of literature were numerically proven for the tested materials and the effect of magnesium content on stress amplitude was analysed in detail.

Effects of magnesium content and carbonation on the multiscale pore structure of alkali-activated slags

While CO2-resistant cement materials are crucial in oil and gas industries, the CO2 emissions associated with manufacturing oil-well cements have necessitated the development of lower-CO2 alternatives with enhanced carbonation resistance. A higher magnesium content blast furnace slag precursor for alkali-activated slag (AAS) has been shown to increase resistance to accelerated carbonation-induced degradation. This investigation assesses the effects of sample age, AAS magnesium content, and carbonation (exposure to 100% CO2) on the multiscale pore structure of AASs (nanometers to microns). The pore size distributions and diffusion tortuosities of ordinary Portland cement (OPC) and silicate-activated slag pastes are obtained through the techniques of nitrogen sorption, mercury intrusion porosimetry, and X-ray microtomography. These pore morphology properties show AAS to be more resistant to pore structural degradation following accelerated carbonation than OPC, and increased magnesium content in AAS is shown to improve its resistance to gel decalcification and capillary pore formation during carbonation.

Enhancing Analytical Performance of (Mg,Fe)3O4/Glassy Carbon Electrodes by Tailoring Chemical Composition of (Mg,Fe)3O4 Nanoparticles

A series of MgxFe3-xO₄ (x ═ 0-1) nanoparticles was synthesized in order to prepare novel MgxFe3-xO₄/glassy carbon modified electrodes. Effects of magnesium content (x) on the analytical performance of the modified electrodes in the detection of gallic acid were evaluated. It was found that magnesium concentration and crystallite/particle size of the prepared nanoparticles play significant roles in the sensing properties of modified electrodes. The increase of magnesium concentration up to the value of x ═ 0.4 in MgxFe3-xO₄/glassy carbon paste was accompanied by an increase of the corresponding oxidation current of gallic acid. However, further growth of x value caused decline of the obtained oxidation current. An electroanalytical procedure was established, and the analytical performance of the proposed Mg0.4Fe2.6O₄/glassy carbon paste electrode was monitored using previously optimized experimental conditions. A working linear range from 1-39 µM gallic acid was obtained with detection limit of 0.29 µM. According to these results, the developed procedure can be applied for detection of low concentrations of gallic acid with satisfactory selectivity in the presence of some common naturally occurring compounds. Experimental results indicate that the developed procedure could be a novel approach in the detection of antioxidant, overcoming some known disadvantages such as passivation, and could be a promising replacement for sophisticated chromatographic methods.

Effect of Magnesium Content on Surface Pattern of Al-Mg Alloy Strips Fabricated by Vertical-Type High-Speed Twin-Roll Casting

Effect of Magnesium Content on Surface Pattern of Al-Mg Alloy Strips Fabricated by Vertical-Type High-Speed Twin-Roll Casting

Effect of magnesium content on keyhole-induced porosity formation and distribution in aluminum alloys laser welding

With the aid of transparent glass, the keyhole behavior and porosity formation are directly observed in laser welding of different aluminum alloys. A three-dimensional model is developed to investigate the recoil pressure change. The influences of Mg element on porosity formation and distribution are discussed based on both numerical and experimental results. During laser welding of aluminum alloys, the molten metal in the front keyhole wall is thick. However, with the increasing Mg content, the weld depth increases in the welding direction, and longer time is required to reach the quasi-steady state; besides, the keyhole is more stable, and less keyhole-induced porosity is formed. Based on pressure balance acting on the keyhole wall, the high recoil pressure contributes to the stability of the keyhole, resulting in the suppression of porosity. Higher density of porosity is formed at the middle and bottom of the weld due to the easier collapse of keyhole in the respective regions in laser welding of aluminum alloys with higher Mg content.

Effect of magnesium content on the microstructure and dry sliding wear behavior of centrifugally cast functionally graded A356-Mg2Si in situ composites

Functionally graded A356 alloy (Al–7.2Si–0.3Mg) –Mg2Si in situ composites have been synthesized via centrifugal casting route. Mg2Si particles tend to migrate towards the core of the tubular product by centrifugal force. The in situ formed Mg2Si particles in composites are characterized by x-ray diffraction (XRD) analysis, Energy dispersive spectrometry (EDS), Optical, Scanning Electron and Transmission Electron Microscopy. Apart from primary blocky Mg2Si particles the matrix contains other phases viz. Al-Si eutectic, pseudo-binary Al-Mg2Si eutectic and Al-Fe-Si intermetallics. Density is found to decrease and %porosity is increased with increase in volume fraction of Mg2Si. Maximum hardness was observed at the inner core region due to maximum segregation of Mg2Si particles and gradually decreases towards the outer periphery region. The dry sliding wear was evaluated with varying parameters such as normal loads (N) and sliding distances (m). A substantial increase in wear resistance at the inner core region is observed. From the worn surface characterization, the wear mechanisms have been explained.

The effect of magnesium content on in vitro bioactivity, biological behavior and antibacterial activity of sol–gel derived 58S bioactive glass

Bioactive glasses (BGs) have a great potential for bone replacement and regeneration in bone tissue engineering applications. In this research, first, sol–gel derived magnesium substituted 58 S BGs (MBGs) series composed of 60SiO2–4P2O5-(36-x) CaO- xMgO, (x = 0; 1; 3; 5; 8 and 10 mol.%) were synthesized and stabilized at 700 °C to eliminate the nitrates and prevent the crystallization of MBGs. MgO was substituted for CaO in the BG formula up to 10 mol% and the effect of Mg concentration on in vitro bioactivity and cellular properties of the MBGs were investigated by immersing them in simulated body fluid (SBF) followed by structural characterization using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) techniques. The effects Mg on proliferation and differentiation of osteoblastic MC3T3-E1 cells were also evaluated by 3-(4,5dimethylthiazol-2-yl)− 2,5-diphenyltetrazolium bromide (MTT) and alkaline phosphate (ALP) activity.Results revealed that magnesium-substituted 58 S BG with 5 mol% MgO (BG-5) had the highest formation rate of hydroxyapatite (HA) while substitution of 8 mol% and10 mol% MgO (BG-8 and BG-10) lowered the bioactivity. MTT and ALP results confirmed that the substitution of the MgO up to 5 mol% increased both proliferation and differentiation of MC3T3-E1 cells, while more substitution had a negative effect and resulted in a decrease of proliferation and differentiation in BG-8 and BG-10. The result of antibacterial test showed that MBGs exhibited antibacterial effect against methicillin-resistant Staphylococcus aureus (MRSA) bacteria. Taken together, results suggest that, among all the synthesized MBGs, sample BG-5 is a promising candidate as multifunctional biomaterial for bone tissue engineering with maximum cell proliferation and ALP activity, good bioactivity and high antibacterial efficiency against MRSA bacteria. Eventually, the BG-5 is suggested to be used in segmental defects in rat model in vivo.

Effect of Magnesium Content and Processing Conditions on Phase Formation and Stability in Mg2+δSi0.3Sn0.7

Mg2+δSi0.3Sn0.7 compositions with nominal Mg content of δ = 0, 0.2 are synthesized using a single-step quartz tube reaction method with different heating rates and holding times. The resulting powders are sintered using a uniaxial induction hot press under similar conditions to produce near-dense compacts. The effect of Mg content and processing conditions on the phase formation and its stability are studied using x-ray diffraction measurements, scanning electron microscopy (SEM) with elemental mapping and compositional analysis using energy dispersive spectroscopy (EDS). Results indicate that with sufficient Mg content and shorter synthesis time, the powder remains single phasic; however, prolonged heat treatment during synthesis results in Mg loss and causes the system to become biphasic. Compaction results in single-phase formation in all the specimens. This is attributed to the removal of the low-melting secondary Sn-rich phases present in the system. The decomposition of the specimens depends on the Mg content after the compaction step with a δ around − 0.15 necessary to preserve the single phase. The decomposition also results in Mg enrichment of the matrix (due to formation of elemental Sn), thereby acting as a self-healing mechanism. Annealing the dense products at 773 K for 24 h in static vacuum is carried out. Progressive Mg loss is observed resulting in degradation of the specimen.

Effects of Magnesium Content on Structure and Electrochemical Properties of La‐Mg‐Pr‐Al‐Mn‐Co‐Ni Hydrogen Storage Alloys

The discharge capacity, microstructures, and corrosion resistance of some as‐cast alloys represented by the formula La0.7−xMgxPr0.3Al0.3Mn0.4Co0.5Ni3.8, where x = 0.0, 0.1, 0.3, 0.5, and 0.7, were investigated by SEM/EDX, XRD, and electrochemical measurements. The partial substitution of La by Mg refined the grain structure while the total substitution changed it from equiaxed to columnar. Three phases were detected: a major phase (M), a grey phase (G), and a dark phase (D). The compositions analyzed by EDX suggested that the M phase was close to a LaNi5 phase. With the increase of the Mg content, the analyses revealed a G phase with composition close to a RMg2Ni9 (R = La,Pr) and a D phase close to a MgNi2 phase. The XRD analysis and Rietveld refinement corroborated the EDX results. The corrosion resistance of the alloys was evaluated in 6.0 mol·L−1 KOH solution, and the results showed that the substitution of La by Mg was beneficial for this alloy property. Nevertheless, Mg addition was deleterious to the discharge capacity of the electrodes.

Effect of magnesium content on bioactivity of near invert phosphate‐based glasses

AbstractA series of phosphate glasses 40P2O5‐(40−x)CaO‐xMgO‐(20−y)Na2O‐yTiO2 (where 0 ≤ x ≤ 24 and y = 0 or 1) with varying MgO contents were investigated for their in vitro calcium phosphate (CaP) formation. Thermal analysis of these glass compositions was conducted and a significant decrease in glass transition temperature from 448°C to 430°C was seen with reducing MgO content from 24 to 8 mol%. Degradation studies were performed in phosphate buffered saline (PBS) at 37°C, where the 8 mol% MgO glass showed the highest mass loss of around 3.4% after 28 days of immersion. Cation release studies were conducted via ion chromatography, using ultrapure water at 37°C as the degradation medium. The highest release of Ca2+ and Na+ ions was observed with the 8 mol% MgO glass. In vitro CaP formation studies were conducted using glass discs immersed in simulated body fluid (SBF) at 37°C for up to 28 days. The amorphous phase and chemical composition of deposited CaP layers on the glass discs were confirmed via X‐ray diffraction (XRD) and energy‐dispersive X‐ray spectroscopy (EDX) analysis, respectively. CaP layers with Ca/P ratio 0.8‐1.1 were found to be deposited on the lower MgO content (8 to 2 mol%) glass surface after 28 days of SBF study.

Effect of Silicon and Magnesium Content on Properties of Aluminum Based Sintered Bearing

Because of light weight and low cost, the aluminum-based oiled bearing has become one of the hot research points in the field of oiled bearing. Due to the shortcomings of aluminum itself, such as low hardness and poor weak bearing capacity and wear-resisting, therefore, Cu, Mg, Si and other elements are needed to add into the aluminum matrix to improve the hollow ratio, radial crushing strength and other performance parameters of oil bearing. In this paper, powder metallurgy method will be used to manufacture Al-Cu oiled bearing, with copper content of 7.5% Al-Cu mixed powder as the base, add Silicon first and study the effect of silicon content on the sinter properties. Then, adding magnesium in Al-Cu-Si substrate and the effect of magnesium content on properties will also be discussed. The research shows that when the matrix of the silicon content is 1.0%, and magnesium content is 2.0%, the aluminum-based oiled bearing that was manufactured has good comprehensive properties.

Effect of Magnesium Content on Machinability of Cu-Zn-Bi-Sb Alloy

In order to develop high-performance lead-free brasses, the effect of magnesium content on the machinability of lead-free brass alloys was carefully studied in the present work. The ingots of the Cu-Zn-Bi-Sb alloy were fabricated in terms of different magnesium contents of 1.0, 2.0, 3.0 and 4.0 wt%. The difference in the machinability of the Cu-Zn-Bi-Sb alloy ingots was discussed in terms of their microstructure, mechanical properties and chip morphologies. X-ray diffraction analysis indicated that α phase (0~38 Zn by atom %), β phase (45~49 Zn by atom %), CuMgSb and CuMgZn existed in the Cu-Zn-Bi-Sb alloys with the different magnesium contents. With increasing the content of magnesium, the machinability of the present lead-free brass alloys was markedly improved, which is mainly attributed to the formation of intermetallic compounds such as CuMgSb and CuMgZn.

Research on the Selection of Heat Treatment Parameters of Casting Aluminum Alloy AlSi5Mg Type

The paper presents research on the effects of magnesium content on electrical and mechanical properties of materials after heat treatment of the casting of aluminum alloys: AlSi5Mg0.3, AlSi5Mg0.8 and AlSi5Mg1. The proposed heat treatment consisted of homogenisation at 535°C during period of the time 8 h, quenched to water and artificial aging at temperatures ranging from 120 to 240°C during period of the time to 24 h. Determination of strength properties were realized by Brinell hardness measurements. Electrical properties are in the form of electrical conductivity. The research program also included analysis of the microstructure of selected alloys.

Development of Aluminum Alloy AA5754 Production with a Different Magnesium Content by a Twin-Roll Casting Process

The effect of magnesium content and different thermomechanical treatment regimes on structure formation for sheet aluminum alloy AA5754 produced by twin-roll casting technology is evaluated. Cast sheets of alloy AA5754 containing 2.8, 3.0, and 3.2 wt.% magnesium 6 mm thick are cold rolled to a thickness of 1 mm. Three thermomechanical treatment regimes and annealing for alloy AA5754 are studied. Specimens obtained by this technology are strength tested. Grain size and distribution within the structure of finished sheet workpieces are determined by a standard procedure. With an increase in magnesium content in specimen grain diameter is considerably reduced. All specimens, prepared by a supplementary production scheme using homogenizing heat treatment in the final annealing stage, have maximum ductility, and also higher values of ultimate and yield strength than for specimens prepared using other production schemes and changed magnesium content.

Effects of Magnesium Content on Ballistic Performance of Al-8Zn-SiC Composite after Heat Treatment Process

SiC – reinforced aluminium composite - has been developed to improve the ballistic performance and mobility of the armour material. Critical to obtaining ballistic resistance is that the materials must be sufficiently hard and strong, especially at the surface where a projectile will first make impact. To achieve this resistance, aluminium alloys can be strengthened by adding Zn and Mg, and reinforced with silicon carbide. This research studied the ballistic properties of aluminium composites with varied Mg. The matrix used in this study was an Al-8Zn alloy with 3-5 wt. % Mg. Silicon carbide particulate of 15 % volume fraction was used as strengthening material, which was added to the liquid matrix by stirring at 5000 rpm. The liquid composite was then squeeze cast at a pressure of 72 MPa. Then the composites were heat-treated and coated to improve the ballistic performance. Ballistic testing was performed in accordance with ASTM F1233 by using 7.62 calibre projectiles. Microstructural observation was conducted in samples, performed with optical microscope. The results showed that the as-cast hardness of the composite increased with addition of Mg content of 3, 4 and 5 wt. %. The peak hardness after ageing at 200 °C also increased with Mg addition. However, the composites were not able to withstand the 7.62 mm calibre projectile.