scholarly journals The Effect of Increased Cu Content on Microstructure and Melting of Utilized Sn-0.3Ag-0.7Cu Solder

2018 ◽  
Vol 26 (43) ◽  
pp. 33-44
Author(s):  
Marián Drienovský ◽  
Lýdia Rízeková Trnková ◽  
Roman Čička ◽  
Pavol Priputen ◽  
Marcela Pekarčíková ◽  
...  
Keyword(s):  
Microstructure Evolution ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Cu Content ◽  
Soldering Process ◽  
Wave Soldering ◽  
Thermo Calc Software ◽  
Temperature Dependences ◽  
Free Solder

Abstract The influence of increased Cu and Ag contents on the microstructure evolution in the utilized Sn-0.3Ag-0.7Cu (wt. %) solder was studied. The utilized solder was exploited in the wave soldering process at the temperatures of about 260 °C for several days. The samples investigation involved the differential scanning calorimetry, the scanning electron microscopy including the energy dispersive X-ray spectroscopy, and the X-ray diffraction techniques. To predict phase equilibria at various temperatures and temperature dependences of heat capacity, the Thermo-Calc software and the COST531 lead-free solder database were used. The original and the utilized solders were found to be very similar regarding the phase occurrence, but slightly differ from one another in microstructure evolution due to higher bulk contents of Cu in the latter solder. The obtained results contribute to both the better understanding of the microstructure evolution in low-silver Sn-Ag-Cu solders and the determination of compositional limits for those solders used in the wave soldering process.

Microstructure Evolution of a Fine Grain Al-50wt%Si Alloy Fabricated by High Energy Milling

2011 ◽  
Vol 479 ◽  
pp. 54-61 ◽  
Author(s):  
Fei Wang ◽  
Ya Ping Wang
Keyword(s):  
Grain Growth ◽  
Microstructure Evolution ◽  
Room Temperature ◽  
Milling Time ◽  
High Energy ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Laser Method ◽  
X Ray ◽  
Fine Grain

Microstructure evolution of high energy milled Al-50wt%Si alloy during heat treatment at different temperature was studied. Scanning electron microscope (SEM) and X-ray diffraction (XRD) results show that the size of the alloy powders decreased with increasing milling time. The observable coarsening of Si particles was not seen below 730°C in the high energy milled alloy, whereas, for the alloy prepared by mixed Al and Si powders, the grain growth occurred at 660°C. The activation energy for the grain growth of Si particles in the high energy milled alloy was determined as about 244 kJ/mol by the differential scanning calorimetry (DSC) data analysis. The size of Si particles in the hot pressed Al-50wt%Si alloy prepared by high energy milled powders was 5-30 m at 700°C, which was significantly reduced compared to that of the original Si powders. Thermal diffusivity of the hot pressed Al-50wt%Si alloy was 55 mm2/s at room temperature which was obtained by laser method.

Microstructure Evolution and Properties of 7A56 Aluminum Alloy by Homogenization

2017 ◽  
Vol 898 ◽  
pp. 153-158 ◽  
Author(s):  
Da Xu ◽  
Zhi Hui Li ◽  
Guo Jun Wang ◽  
Long Bing Jin ◽  
Hong Wei Yan ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Microstructure Evolution ◽  
Equilibrium Phase ◽  
Hardness Test ◽  
Homogenization Temperature ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Second Phases ◽  
Al Matrix

The microstructure evolution and properties of Al-matrix in homogenized 7A56 alloy were investigated by scanning electron microscope (SEM), X-ray diffraction (XRD), differential scanning calorimetry (DSC), electrical conductivity and hardness test. The second phases in as-cast 7A56 alloy consisted of AlZnMgCu, Al2Cu and Al7Cu2Fe. With the homogenization temperature increasing, more non-equilibrium phase AlZnMgCu was dissolved into Al-matrix. The diffusion of alloying elements from AlZnMgCu phase into Al-matrix leads to a decrease of electrical conductivity and an increase of hardness. The lattice constant of α-Al has an increases of 0.0019 Å, 0.0032 Å and 0.0053 Å after 380°C/24h,430°C/24h,and 470°C/24 h treatment,respectively.

Characterization of Indium addition on Sn-Bi-Sb Lead free Solder alloy

2016 ◽  
Vol 12 (2) ◽  
pp. 4231-4243 ◽  
Author(s):  
Sara Mosaad Mahlab ◽  
Mustafa Kamal ◽  
Abd El-Raouf Mohamed Mansour
Keyword(s):  
Elastic Moduli ◽  
Resonance Method ◽  
Lead Free Solder ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Lead Free Solder Alloy ◽  
Free Solder ◽  
Rapidly Solidified

The aim of these work is to measure the effect of the addition of In with different atomic percent weight on structure, melting, Electrical and mechanical properties of Sn70-X at.% -Bi15 at.% -Sb15 at.%- Inx at.%  rapidly solidified. X-ray diffraction analysis (XRD), differential scanning calorimetry (DSC), temperature dependence of resistivity (TDR), and mechanical resonance method are performed. It's found that electrical conductivity (σ) and thermal conductivity (K) increased gradually by increasing In at.%. Melting temperature reduced from 470.12 K for Sn70 at.%- Bi15 at.%- Sb15 at.% to 427.13 K in Sn61 at.%- Bi15 at.%- Sb15 at.%- In9 at.%. Also, elastic moduli, internal friction and thermal diffusivity measured from melt-quenched ribbons. 

scholarly journals Effect Of 3% Molybdenum (Mo) Nanoparticles on The Melting, Microstructure and Hardness Properties of As- Reflowed Low Mass Sn-58Bi (SB) Solder Alloy

2020 ◽  
Vol 77 (1) ◽  
pp. 69-87
Author(s):  
Amares Singh ◽  
Rajkumar Durairaj ◽  
How Kuan Seng
Keyword(s):  
Solder Alloy ◽  
Vickers Microhardness ◽  
Dispersion Strengthening ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Lamellar Structures ◽  
Low Mass ◽  
Packaging Industry ◽  
Free Solder

The Sn-58Bi (SB) lead free solder alloy tested in this research with addition of 3% Molybdenum (Mo) nanoparticles equivalent to 0.6g mass to analyse the influences in the thermal, microstructure and microhardness. Elevation of 3.8°C was observed from the Differential Scanning Calorimetry (DSC) for the 3% Mo nanoparticles added SB solder alloy compared to the bare Sn-58Bi (SB) solder alloy that has a melting temperature of 142.25°C. The microstructures of the reinforced SB solder alloy were refined with closer lamellar structures of ?-Sn and Bi phases compared to the unreinforced SB solder. The SEM/EDX and X-ray Diffraction (XRD) results validate the presence of the 3% Mo nanoparticles in the SB solder. Mechanical properties by means of Vickers microhardness of the Mo reinforced solder alloy showed an increment in hardness value by 2% compared to the bare SB solder alloy. The presence of 3% Mo as discrete particles (dispersion strengthening) contributes to the increase on the hardness value. The introduction of 3% Mo in to the SB solder alloy resulted in increase in the hardness due to the refinement of the microstructure and at the same time allows low temperature soldering in the electronic packaging industry.

CRYSTALLIZATION BEHAVIOR OF AMORPHOUS TI-NI-CU ALLOY RIBBONS

2008 ◽  
Vol 01 (02) ◽  
pp. 145-149 ◽  
Author(s):  
JUNG MIN NAM ◽  
YONG HEE LEE ◽  
TAE HYUN NAM ◽  
YEON WOOK KIM ◽  
JUNG MOO LEE
Keyword(s):  
Melt Spinning ◽  
Crystallization Behavior ◽  
Glass Forming Ability ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Cu Content ◽  
Glass Forming ◽  
Cu Alloy ◽  
Transmission Electron

Amorphous Ti 50 Ni (50-x) Cu x (at.%) (x = 15, 20 and 25) alloy ribbons were prepared by melt spinning, and then their crystallization behavior was investigated by optical microscopy, transmission electron microscopy, X-ray diffraction and differential scanning calorimetry. Wavenumber (Qp) decreased from 29.40 nm-1 to 29.29 nm-1 and ΔT(T g - T x ) increased from 31 K to 36 K with increasing Cu content from 15 at.% to 25 at.%, suggesting that glass forming ability of Ti – Ni – Cu alloy ribbons increased with increasing Cu content. Activation energy for crystallization decreased from 211.5 kJ/mol to 136.4 kJ/mol with increasing Cu content from 15 at.% to 25 at.%, suggesting that a stability of Ti – Ni – Cu amorphous decreased with increasing Cu content.

Studies on the Preparation, Characterization and Solubility of -Cyclodextrin-Roxythromycin Inclusion Complexes

2009 ◽  
Vol 2 (2) ◽  
pp. 523-530
Author(s):  
D. Nagasamy Venkatesh ◽  
S. Karthick ◽  
M. Umesh ◽  
G. Vivek ◽  
R.M. Valliappan ◽  
...  
Keyword(s):  
Dissolution Rate ◽  
Inclusion Complexes ◽  
Phase Solubility ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Ir Studies ◽  
Poorly Soluble ◽  
Poorly Soluble Drug

Roxythromycin/ β-cyclodextrin (Roxy/ β-CD) dispersions were prepared with a view to study the influence of β-CD on the solubility and dissolution rate of this poorly soluble drug. Phase-solubility profile indicated that the solubility of roxythromycin was significantly increased in the presence of β-cyclodextrin and was classified as AL-type, indicating the 1:1 stoichiometric inclusion complexes. Physical characterization of the prepared systems was carried out by differential scanning calorimetry (DSC), X-ray diffraction studies (XRD) and IR studies. Solid state characterization of the drug β-CD binary system using XRD, FTIR and DSC revealed distinct loss of drug crystallinity in the formulation, ostensibly accounting for enhancement of dissolution rate.

scholarly journals A review of nanotechnology with an emphasis on Nanoplex

2015 ◽  
Vol 51 (2) ◽  
pp. 255-263
Author(s):  
Rupali Nanasaheb Kadam ◽  
Raosaheb Sopanrao Shendge ◽  
Vishal Vijay Pande
Keyword(s):  
Drug Delivery ◽  
Drug Delivery Systems ◽  
Drug Loading ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Conventional Drug ◽  
Anionic Drugs ◽  
Oppositely Charged ◽  
The Brain

<p>The use of nanotechnology based on the development and fabrication of nanostructures is one approach that has been employed to overcome the challenges involved with conventional drug delivery systems. Formulating Nanoplex is the new trend in nanotechnology. A nanoplex is a complex formed by a drug nanoparticle with an oppositely charged polyelectrolyte. Both cationic and anionic drugs form complexes with oppositely charged polyelectrolytes. Compared with other nanostructures, the yield of Nanoplex is greater and the complexation efficiency is better. Nanoplex are also easier to prepare. Nanoplex formulation is characterized through the production yield, complexation efficiency, drug loading, particle size and zeta potential using scanning electron microscopy, differential scanning calorimetry, X-ray diffraction and dialysis studies. Nanoplex have wide-ranging applications in different fields such as cancer therapy, gene drug delivery, drug delivery to the brain and protein and peptide drug delivery.</p>

scholarly journals Diethylstilbestrol Modifies the Structure of Model Membranes and Is Localized Close to the First Carbons of the Fatty Acyl Chains

Biomolecules ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 220
Author(s):  
Alessio Ausili ◽  
Inés Rodríguez-González ◽  
Alejandro Torrecillas ◽  
José A. Teruel ◽  
Juan C. Gómez-Fernández
Keyword(s):  
Membrane Surface ◽  
Water Layer ◽  
Fatty Acyl ◽  
31P Nmr Spectroscopy ◽  
Relaxation Rates ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Acyl Chains ◽  
Dynamics Simulations

The synthetic estrogen diethylstilbestrol (DES) is used to treat metastatic carcinomas and prostate cancer. We studied its interaction with membranes and its localization to understand its mechanism of action and side-effects. We used differential scanning calorimetry (DSC) showing that DES fluidized the membrane and has poor solubility in DMPC (1,2-dimyristoyl-sn-glycero-3-phosphocholine) in the fluid state. Using small-angle X-ray diffraction (SAXD), it was observed that DES increased the thickness of the water layer between phospholipid membranes, indicating effects on the membrane surface. DSC, X-ray diffraction, and 31P-NMR spectroscopy were used to study the effect of DES on the Lα-to-HII phase transition, and it was observed that negative curvature of the membrane is promoted by DES, and this effect may be significant to understand its action on membrane enzymes. Using the 1H-NOESY-NMR-MAS technique, cross-relaxation rates for different protons of DES with POPC (1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine) protons were calculated, suggesting that the most likely location of DES in the membrane is with the main axis parallel to the surface and close to the first carbons of the fatty acyl chains of POPC. Molecular dynamics simulations were in close agreements with the experimental results regarding the location of DES in phospholipids bilayers.

scholarly journals Effects of Sintering Temperature on Densification, Microstructure and Mechanical Properties of Al-Based Alloy by High-Velocity Compaction

Metals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 218
Author(s):  
Xianjie Yuan ◽  
Xuanhui Qu ◽  
Haiqing Yin ◽  
Zaiqiang Feng ◽  
Mingqi Tang ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
High Velocity ◽  
Sintered Density ◽  
Sintering Temperature ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Transmission Electron ◽  
High Velocity Compaction ◽  
Sintered Temperature

This present work investigates the effects of sintering temperature on densification, mechanical properties and microstructure of Al-based alloy pressed by high-velocity compaction. The green samples were heated under the flow of high pure (99.99 wt%) N2. The heating rate was 4 °C/min before 315 °C. For reducing the residual stress, the samples were isothermally held for one h. Then, the specimens were respectively heated at the rate of 10 °C/min to the temperature between 540 °C and 700 °C, held for one h, and then furnace-cooled to the room temperature. Results indicate that when the sintered temperature was 640 °C, both the sintered density and mechanical properties was optimum. Differential Scanning Calorimetry, X-ray diffraction of sintered samples, Scanning Electron Microscopy, Energy Dispersive Spectroscopy, and Transmission Electron Microscope were used to analyse the microstructure and phases.

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