A novel Mg-Sn-Zn-Al-Mn magnesium alloy with superior corrosion properties

2021 ◽  
Vol 118 (5) ◽  
pp. 504
Author(s):  
Ali Ercetin

The corrosion behaviors of the hot-pressed Mg-Sn-Zn-Al-Mn magnesium alloys with the addition of Al in different proportions have been investigated. Paraffin coating technique was applied to Mg powders before production. After debinding at 300 °C, the sintering process was applied at 610 °C under 50 MPa pressure for 70 min. All of the alloys were immersed in Hank’s solution for 10-days. The results indicated that the corrosion properties of the alloys were affected by the production method (hot pressing) and alloying element addition. After immersion, magnesium hydroxide (Mg(OH)2), hydroxyapatite (HA), and Mg-Al hydrotalcite structures were determined by the X-ray diffraction (XRD) analysis on the surfaces of Mg-Sn-Zn-Al-Mn alloys. The Mg-Al hydrotalcite protective layer was effective in preventing corrosion. Superior corrosion properties (weight loss: 1.2%, total volume of evolved H2 gas: 4 ml/cm2, corrosion rate: 0.39 mm/year) were obtained from TZAM5420 alloy (5 wt.%Sn, 4 wt.%Zn, 2 wt.%Al, 0.2 wt.%Mn).

Metals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 852
Author(s):  
Asiful H. Seikh ◽  
Hossam Halfa ◽  
Mahmoud S. Soliman

Molybdenum (Mo) is an important alloying element in maraging steels. In this study, we altered the Mo concentration during the production of four cobalt-free maraging steels using an electroslag refining process. The microstructure of the four forged maraging steels was evaluated to examine phase contents by optical microscopy, scanning electron microscopy (SEM), and X-ray diffraction (XRD) analysis. Additionally, we assessed the corrosion resistance of the newly developed alloys in 3.5% NaCl solution and 1 M H2SO4 solution through potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques. Furthermore, we performed SEM and energy-dispersive spectroscopy (EDS) analysis after corrosion to assess changes in microstructure and Raman spectroscopy to identify the presence of phases on the electrode surface. The microstructural analysis shows that the formation of retained austenite increases with increasing Mo concentrations. It is found from corrosion study that increasing Mo concentration up to 4.6% increased the corrosion resistance of the steel. However, further increase in Mo concentration reduces the corrosion resistance.


2012 ◽  
Vol 512-515 ◽  
pp. 390-394 ◽  
Author(s):  
Ya Yun Li ◽  
Bo Li ◽  
Jing Bo Sun ◽  
Kun Peng Cai ◽  
Ji Zhou ◽  
...  

A kind of aqueous based suspensions of lead lanthanum zirconnate titanate (PLZT) was developed for direct ink writing (DIW) assembly. Piezoelectric ceramic woodpile structures with diameter of 315-470μm were fabricated from these inks by using DIW. The preparation of aqueous based piezoelectric inks, the principle of DIW and the sintering process were systematically discussed. The ink with solids volume fraction over 70% by 1 day aging reveals shear-thinning behavior and proper viscoelastic properties, which ensures a feasible extrusion in the whole shaping process. The PLZT samples sintered at varying temperatures between 1150 oC and 1250 oC for 2h or 4 h in either air or a lead-rich atmosphere yielded various microstructures observed by scanning electron microscopy (SEM). Choosing the optimum sintering condition, the sintered products were densified with relative density exceed 98%. The test of X-ray diffraction (XRD) analysis reveals that the main phase of sintered samples is rhombohedral Pb0.93La0.07(Zr0.65Ti0.35)0.9825O3. The direct ink writing technique has advantages of good design ability and rapid forming capability, which opens up a potential route for the design and fabrication of piezoelectric devices.


Materials ◽  
2020 ◽  
Vol 13 (23) ◽  
pp. 5413
Author(s):  
Rabiatul Adawiyah Abdul Wahab ◽  
Mohd Hafiz Mohd Zaid ◽  
Sidek Hj. Ab Aziz ◽  
Khamirul Amin Matori ◽  
Yap Wing Fen ◽  
...  

In this study, the authors attempted to propose the very first study on fabrication and characterization of zinc-boro-silicate (ZBS) glass-ceramics derived from the ternary zinc-boro-silicate (ZnO)0.65(B2O3)0.15(RHA)0.2 glass system through a conventional melt-quenching method by incorporating rice husk ash (RHA) as the silica (SiO2) source, followed by a sintering process. Optimization of sintering condition has densified the sintered samples while embedded beta willemite (β-Zn2SiO4) and alpha willemite (α-Zn2SiO4) were proven in X-ray diffraction (XRD) analysis. Field emission scanning electron microscopy (FESEM) has shown the distribution of willemite crystals in rhombohedral shape crystals and successfully form closely-packed grains due to intense crystallization. The photoluminescence (PL) spectra of all sintered ZBS glasses presented various emission peaks at 425, 463, 487, 531, and 643 nm corresponded to violet, blue, green, and red emission, respectively. The correlation between the densification, phase transformation, microstructure, and photoluminescence of Zn2SiO4 glass-ceramic phosphor is discussed in detail.


2014 ◽  
Vol 12 (11) ◽  
pp. 1183-1193 ◽  
Author(s):  
Vassil Bachvarov ◽  
Miglena Peshova ◽  
Stefana Vitkova ◽  
Nikolai Boshkov

AbstractThe presented work reports on the peculiarities of the anodic behavior, corrosion resistance and protective ability of electrodeposited Zn-Ni-P alloys with a different composition in a model corrosion medium of 5% NaCl. Three characteristic coating types have been investigated using experimental methods such as potentiodynamic polarization (PD) technique and polarization resistance (Rp) measurements. In addition, X-ray diffraction (XRD) analysis as well as scanning electron microscopy (SEM) coupled with an Energy-dispersive X-ray (EDAX) device were applied to determine the differences in the chemical composition and surface morphology which appeared as a result of the corrosion treatment. The data obtained are compared to those of electrodeposited pure Zn coatings with identical experimental conditions demonstrating the enhanced protective characteristics of the ternary alloys during the test period in the model medium. The influence of the chemical and phase composition of the alloys on its corrosion resistance and protective ability is also commented and discussed.


Author(s):  
Franciska Pramuji Lestari ◽  
Sofia Marta ◽  
Aprilia Erryan ◽  
Inti Mulyati ◽  
Ika Kartika

Magnesium alloys have been intensively studied as possible resorbable material with adequate mechanical properties similar to natural bones but very poor corrosion properties. In this analysis, the addition of Zn element to quaternary Mg-Ca-Zn alloy foam was evaluated with TiH2 as a foaming agent and manufactured with high-purity raw materials the powder metallurgy process. In Hank's solution, the rate of corrosion of specimens by direct observations with Scanning Electron Microscopy ( SEM), Electron Dispersion Spectrometry (EDS), static immersion studies, potentiodynamic evaluations, and X-Ray Diffraction (XRD). The specimens post-immersion characteristics and the corresponding Hank's solutions were examined at 2, 4, 6, 24, 48, and 72 hours of immersion. The findings show that the microstructure of alloy morphology, such as pores, pitting corrosion, needle shapes, and galvanic corrosion has the main corrosion products Mg(OH)2 and Ca10(PO4)6(OH)2. The addition of less than 6 percent wt Zn will minimize the corrosion rate but increase with 10 percent wt Zn. From this study, Mg-Zn-Ca alloy at 6 percent wt Zn has the lowest corrosion rate with slow pH changes in the process.


2013 ◽  
Vol 829 ◽  
pp. 605-609 ◽  
Author(s):  
Mohamad Fatahi Amirdehi ◽  
Darush Afzali

In the present century many efforts have been done to develop efficient methods for corrosion protection of steel in various industries. The use of conducting polymers is one of the new developments in the area. In this study, polyaniline/silica nanocomposite has been coated onto 316L stainless steel via in situ method. The corrosion behaviors of the bare and coated steels have been studied in order to reveal influence of silica nanoparticles (70nm).The prepared coating has been characterized using X-ray diffraction (XRD). The corrosion performance of the coating has been investigated in 1 M H2SO4 solution by using electrochemical impedance spectroscopy (EIS). It was found that protecting effect of coated layer is influenced by amounts of silica nanoparticles.


2021 ◽  
Vol 55 (3) ◽  
Author(s):  
Xiao Wang ◽  
Yixiao Xie ◽  
Weiwei Cong ◽  
Zhaolei Li ◽  
Zexiao Xu ◽  
...  

With the development of science and technology and the ever-increasing focus of the environmental protection, waterborne acrylic resin based coating has been commonly used in a wide range of applications due to its high flexibility and good UV resistance. Continuous attempts have been extensively carried out to improve its corrosion resistance and mechanical properties through doping of different nanomaterials. In this study, Functionalized Graphene Oxide (FGO) nanosheets covalently bonded to hydroxylated acrylic resin was introduced into the Hydroxyacrylic Acid Dispersion (HAD) matrix to enhance the performance. To study the effect of grafted hydroxylated acrylic resin on morphology and properties of GO nanosheets, the GO and FGO nanosheets have been systematically characterized with various testing methods, such as FTIR, field emission-scanning electron microscopy (FE-SEM), transmission electron microscope (TEM), Raman spectroscopy, X-ray diffraction (XRD) analysis, UV–vis analysis, and thermogravimetric analysis (TGA). The morphology, physical–mechanical, and anti-corrosion properties of the HAD coatings doped with GO and FGO nanosheets have been compared. The results confirmed that FGO’s dispersion behavior in the HAD matrix has been improved after modifification with the hydroxylated acrylic resin, and the interfacial bonds between the HAD-FGO nanosheets have been significantly enhanced.


2014 ◽  
Vol 627 ◽  
pp. 18-23
Author(s):  
M.R.N. Liyana ◽  
Nur Maizatul Shima Adzali ◽  
W. Rahman ◽  
M.Z.M. Zamzuri ◽  
Harun Azmi

Microwave heating technology promising shorter processing times and less energy consumption beneficial for economic perspective with improved properties and better microstructural control. This study focussed on microwave sintered bioceramics material of 60YSZ-Al2O3/10HAP mixture fabricated by powder metallurgy route. The study was conducted based on three different sintering temperatures, starting with 900 °C, 1000°C ended with 1100°C. Mechanical properties of materials such as porosity, density, hardness and compressive strength were then determined for each composites. Results showed that lowest porosity was obtained at 1000°C which promoting to higher density, hardness and compressive strength. However, the increasing sintering temperature up to 1100 °C was initiated the decomposition of HAP and constitutes the formation of CaZrO3determined by X-ray Diffraction (XRD) analysis. Microstructure characterization by Scanning Electron Microscope (SEM) observed the growth of large particles and pores result in excessive grain coarsening. Better sinterability was achieved through an adequate sintering temperature of 1000°C with no reaction reported between HA and ZrO2during the sintering process facilitate by microwave hybrid heating. The pores was found to be interconnected for each composites via microwave heating expected to be useful for biomedical application which was favorable to osteo-integration.


2012 ◽  
Vol 626 ◽  
pp. 275-279 ◽  
Author(s):  
Zulkifli Mohd Rosli ◽  
Zainab B. Mahamud ◽  
Jariah Mohd Juoi ◽  
Nayan Nafarizal ◽  
Kwan Wai Loon ◽  
...  

Magnesium alloys create increasing interest in structural application where weight reduction is vast concern. However, its low corrosion resistance especially in atmosphere environment restricts their wide application. In this study, AlN and TiN were coated on AZ91 Mg alloy using PVD magnetron sputtering. AlN and TiN existence is confirmed via grazing angle x-ray diffraction (GA-XRD). The corrosion behaviors of uncoated and coated AZ91 Mg alloy in3.5% NaCl and Hanks solutions were investigated using a potentiostat during electrochemical corrosion test. AlN and TiN coated samples showed better performance in Hanks solution with TiN coated samples have the least corrosion rate (penetration rate=0.040mm/yr and mass loss rate=0.191g/m2d) in Hanks solution. These create interest to further works on exploring the potential of coated AZ91 Mg alloy in biomaterial application.


2016 ◽  
Vol 61 (3) ◽  
pp. 1437-1440 ◽  
Author(s):  
K. Kowalski ◽  
M. Nowak ◽  
M. Jurczyk

Abstract Magnesium alloys have recently attracted much attention as a new generation of biodegradable metallic materials. In this work, Mg1Mn1Zn0.3Zr-bioceramic nanocomposites and their scaffolds were synthesized using a combination of mechanical alloying and a space-holder sintering process. The phase and microstructure analysis was carried out using X-ray diffraction, scanning electron microscopy and the properties were measured using hardness and corrosion testing equipment. Nanostructured Mg-bioceramic composites with a grain sizes below 73 nm were synthesized. The Vickers hardnesses for the bulk nanostructured Mg-based composites are two times greater than that of pure microcrystalline Mg metal (50 HV0.3). Produced Mg-based bionanomaterials can be applied in medicine.


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