Modification of Pb-Sb eutectic bearing-solder alloys with bismuth additions rapidly solidified from melt

2015 ◽  
Vol 10 (1) ◽  
pp. 2523-2533
Author(s):  
Rizk El- Sayed ◽  
Bilal W. Mahdi ◽  
Abu-Bakr El-Bediwi ◽  
Mustafa Kamal

In this work, various amounts of Bi element have been added to the eutectic Pb-Sb to form bearing- solder materials. The Pb-Sb eutectic has been produced by rapid solidification using melt spinning technique with various amounts of Bi have been added to it, in the ratio 1, 2 , 3, 4, and 5 wt.%. Scanning electron microscopy (SEM), X- ray diffraction (XRD) analysis and differential scanning calorimetry (DSC) have been carried out.  Microhardness measurements were also carried out using Vicker’s hardness technique.  The results showed that, the ternary alloys up to 4 wt.% Bi  have properties superior to binary eutectic material.   Bismuth up to 4wt. % increases the Young’s modulus, Vicker’s hardness and decreases the electrical resistivity, internal friction and melting point.  The ternary Pb-13.1Sb-4Bi solder alloy has a lower melting point about 237.87 ˚C. Also, the results show that formation of Bi phase developed the mechanical properties and Vicker’s hardness due to addition of Bi element.   The addition of Bi refines the crystal size of Sn in case of melt spun alloys as seen in scanning electron micrographs and X-ray diffraction.

2011 ◽  
Vol 2011 ◽  
pp. 1-8 ◽  
Author(s):  
Hassan Ilyas ◽  
Ishtiaq A. Qazi ◽  
Wasim Asgar ◽  
M. Ali Awan ◽  
Zahir-ud-din Khan

Pure and Ag-TiO2nanoparticles were synthesized, with the metallic doping being done using the Liquid Impregnation (LI) method. The resulting nanoparticles were characterized by analytical methods such as scanning electron micrographs (SEMs), Energy Dispersive Spectroscopy (EDS), and X-ray diffraction (XRD). XRD analysis indicated that the crystallite size ofTiO2was 27 nm to 42 nm while the crystallite size of Ag-TiO2was 11.27 nm to 42.52 nm. The photocatalytic activity of pureTiO2and silver dopedTiO2was tested by photocatalytic degradation ofp-nitrophenol as a model compound. Ag-TiO2nanoparticles exhibited better results (98% degradation) as compared to pureTiO2nanoparticles (83% degradation) in 1 hour for the degradation ofp-nitrophenol. Ag-TiO2was further used for the photocatalytic degradation of 2,4-dichlorphenol (99% degradation), 2,5-dichlorophenol (98% degradation), and 2,4,6-trichlorophenol (96% degradation) in 1 hour. The degree of mineralization was tested by TOC experiment indicating that 2,4-DCP was completely mineralized, while 2,5-DCP was mineralized upto 95 percent and 2,4,6-TCP upto 86 percent within a period of 2 hours.


1999 ◽  
Vol 14 (5) ◽  
pp. 1805-1813 ◽  
Author(s):  
Florence Fusalba ◽  
Daniel Bélanger

A novel polyaniline-molybdenum trisulfide composite has been prepared by chemical polymerization from an acidic (1 M HCl) aqueous solution containing aniline and ammonium tetrathiomolybdate. The presence of molybdenum trisulfide in the polyaniline matrix induces morphological change to the polymer as evidenced by scanning electron micrographs. X-ray diffraction and differential scanning calorimetry indicate that polyaniline-molybdenum trisulfide is slightly less crystalline than polyaniline-HCl. X-ray photoelectron spectroscopy (XPS) and elemental analysis have been used to confirm the presence of molybdenum trisulfide in the polymer matrix. The XPS data also confirm that molybdenum trisulfide and tetrathiomolybdate anions are present with polyaniline to form a new inorganic-organic composite.


Minerals ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 533 ◽  
Author(s):  
Xin Zhang ◽  
Guanghui Li ◽  
Jinxiang You ◽  
Jian Wang ◽  
Jun Luo ◽  
...  

Ludwigite ore is a typical low-grade boron ore accounting for 58.5% boron resource of China, which is mainly composed of magnetite, lizardite and szaibelyite. During soda-ash roasting of ludwigite ore, the presence of lizardite hinders the selective activation of boron. In this work, lizardite and szaibelyite were prepared and their soda-ash roasting behaviors were investigated using thermogravimetric-differential scanning calorimetry (TG-DSC), X-ray diffraction (XRD), and scanning electron microscope and energy dispersive spectrometer (SEM-EDS) analyses, in order to shed light on the soda-ash activation of boron within ludwigite ore. Thermodynamics of Na2CO3-MgSiO3-Mg2SiO4-Mg2B2O5 via FactSage show that the formation of Na2MgSiO4 was preferential for the reaction between Na2CO3 and MgSiO3/Mg2SiO4. While, regarding the reaction between Na2CO3 and Mg2B2O5, the formation of NaBO2 was foremost. Raising temperature was beneficial for the soda-ash roasting of lizardite and szaibelyite. At a temperature lower than the melting of sodium carbonate (851 °C), the soda-ash roasting of szaibelyite was faster than that of lizardite. Moreover, the melting of sodium carbonate accelerated the reaction between lizardite with sodium carbonate.


2021 ◽  
pp. 095400832110055
Author(s):  
Yang Wang ◽  
Yuhui Zhang ◽  
Yuhan Xu ◽  
Xiucai Liu ◽  
Weihong Guo

The super-tough bio-based nylon was prepared by melt extrusion. In order to improve the compatibility between bio-based nylon and elastomer, the elastomer POE was grafted with maleic anhydride. Scanning Electron Microscopy (SEM) and Thermogravimetric Analysis (TGA) were used to study the compatibility and micro-distribution between super-tough bio-based nylon and toughened elastomers. The results of mechanical strength experiments show that the 20% content of POE-g-MAH has the best toughening effect. After toughening, the toughness of the super-tough nylon was significantly improved. The notched impact strength was 88 kJ/m2 increasing by 1700%, which was in line with the industrial super-tough nylon. X-ray Diffraction (XRD) and Differential Scanning Calorimetry (DSC) were used to study the crystallization behavior of bio-based PA56, and the effect of bio-based PA56 with high crystallinity on mechanical properties was analyzed from the microstructure.


Author(s):  
M. Shah ◽  
D. Patel

Oxcarbazepine has low solubility and low oral bioavailability, so it’s a challenge to formulate suitable dosage form. In this present investigation, to improve the dissolution rate and solubility, skimmed milk is used as a carrier. Physical mixers were prepared using various drugs to carrier ratio and spray drying technology was used to develop solid dispersion with the carrier. Various techniques were used to characterize the solid dispersion immediately after they were made which includes differential scanning calorimetry, scanning electron microscopy, fourier transform infra- red spectroscopy, X-ray diffraction and in-vitro dissolution profiles. The differential scanning calorimetry thermograms of raw drug indicated of its anhydrous crystalline nature. In thermograms of solid dispersion, the characteristic peak was absent suggesting the change from crystalline nature to amorphous form. X-ray diffraction confirmed those results. X-ray diffraction results of raw drug showed highly intense peak characteristic of its crystalline nature where solid dispersion showed less intense, more diffused peak indicating the change in crystalline form. Fourier transforms infra-red spectroscopy studies showed there was no interaction between drug and carrier. Scanning electron microscopy support the amorphous nature of mixer. The whole formulation showed distinct enhancement in the drug release behavior and solubility. The optimum oxcarbazepine to skimmed milk ratio 1:3 enhances the in-vitro drug release by 3.5 fold and also show distinct increase in solubility. It was concluded that for improvement of solubility of poorly water soluble oxcarbazepine, skimmed milk powder as a carrier can be utilize very well.


Chemija ◽  
2019 ◽  
Vol 30 (2) ◽  
Author(s):  
Andrius Laurikėnas ◽  
Fatma Yalçin ◽  
Robertas Žilinskas ◽  
Ayse Uztetik Morkan ◽  
Albinas Žilinskas ◽  
...  

The solvothermal synthesis between Me(NO3)x ∙ yH2O (Mex+ = Fe3+, Ni2+, Mn2+, Co2+, Cu2+) and respectively 4-nitrosalycilic (4NSA) and 5-sulfosalicylic (5SSA) acids produced hybrid organic-inorganic compounds composed of Mex+ ions and organic fragments which include three different functional groups, carboxylic, hydroxyl and sulfonic, each coordinated to the Mex+ ions. The phase and chemical composition, microstructure and properties of Me2(H2O)4(5SSA)3·DMF and Me2(H2O)4(4NSA)2·DMF (DMF – dimethylformamide) hybrid compounds were evaluated and discussed. The synthesised materials were characterised by X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM) and nuclear magnetic resonance (NMR) spectroscopy. The catalytic properties of the obtained compounds were also investigated.


Coatings ◽  
2018 ◽  
Vol 8 (9) ◽  
pp. 305 ◽  
Author(s):  
Yan Zhang ◽  
Hui Zhang ◽  
Fang Wang ◽  
Li-Xia Wang

The ginger essential oil/β-cyclodextrin (GEO/β-CD) composite, ginger essential oil/β-cyclodextrin/chitosan (GEO/β-CD/CTS) particles and ginger essential oil/β-cyclodextrin/chitosan (GEO/β-CD/CTS) microsphere were prepared with the methods of inclusion, ionic gelation and spray drying. Their properties were studied by using scanning electron microscopy (SEM), differential scanning calorimetry (DSC), thermo-gravimetry analysis (TGA), Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD). The results showed that the particle size of GEO/β-CD composite was smaller than that of β-CD and GEO/β-CD/CTS particles were loose and porous, while the microsphere obtained by spray drying had certain cohesiveness and small particle size. Besides, results also indicated that β-CD/CTS could modify properties and improve the thermal stability of GEO, which would improve its application value in food and medical industries.


2019 ◽  
Vol 969 ◽  
pp. 169-174
Author(s):  
R. Sivanand ◽  
S. Chellammal ◽  
S. Manivannan

In this paper, the effect of size variation of cadmium sulphide nanocrystallites which have been prepared by precipitation method is analyzed. These prepared samples were studied using X-ray diffraction (XRD), Scanning electron microscopy (SEM), and Energy dispersive analysis of spectroscopy (EDAX) techniques. SEM analysis represents the morphological nature of prepared samples and EDAX indicates the confirmation of elements present in the sample. XRD analysis determines the size of the samples and identifies the structure using miller indices (h k l values) of the nanocrystallies matches with JCPDS. From the XRD analysis, the size variation which depends on dopant, capping agent are discussed and corresponding results are reported in this paper.


2012 ◽  
Vol 7 (3) ◽  
pp. 155892501200700 ◽  
Author(s):  
Sanjukta Chatterjee ◽  
Felix A. Reifler ◽  
Bryan T. Chu ◽  
Rudolf Hufenus

This paper addresses the influence of carbon nanotubes (CNT) on the structure and mechanical properties of high tensile strength thermoplastic polymer fibers. Polyamide (PA) fibers with different draw ratios, with and without CNTs as fillers, and having mechanical properties close to industrial standards were spun in a pilot melt spinning plant. The morphology of the fibers was investigated using optical microscopy, nuclear magnetic resonance (NMR) and 2-D wide angle x-ray diffraction (WAXD). Differential scanning calorimetry (DSC) was carried out to get an estimate of the crystallinity. For a concise interpretation of the results of the tensile measurements performed on the fibers, a parameter was developed to account for the detrimental influence of polymer extrusion on their mechanical properties. The CNTs seemed to act as sites for the growth of un-oriented crystalline domains converted from oriented regions, without yielding a mechanical reinforcing effect.


2012 ◽  
Vol 616-618 ◽  
pp. 1732-1735 ◽  
Author(s):  
Xi Hai Shen ◽  
Yu Gang Zheng ◽  
Liang Chang ◽  
Jin Jia Guo ◽  
Song Bin Ye ◽  
...  

Aiming at the glass-to-metal seals serving in the Solar Thermal Power (STP), glass-to-metal vacuum brazed joints were studied. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis were performed to examine the microstructure and element contents of interface seam on the glass-to-metal vacuum brazed joints. Also, the compositional concentration of the interface seam was measured by using energy dispersive spectroscopy (EDS).


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