Introduction to Silver
Silver is a white, shiny metal. Silver's chemical and physical properties are very stable, having very good electrical and thermal conductivity, softness, and high ductility, and its reflectivity is extremely high, up to over 99%. It finds application in many important uses.
Physical Properties of Element Silver (Ag)
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Property
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Value
|
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Melting Point
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961.93°C
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|
Boiling Point
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2212°C
|
|
Relative Density (water=1)
|
10.49
|
|
Heat of Vaporization
|
250.58kJ/mol
|
|
Heat of Fusion
|
11.3kJ/mol
|
|
Vapor Pressure
|
0.34Pa (1234K)
|
|
Speed of Sound
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2600m/s (293.15K)
|
|
Reflectivity
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99%
|
|
Electrical Resistivity
|
1.586×10-8Ω·m (20°C)
|
|
Electronegativity
|
1.93
|
|
Specific Heat Capacity
|
232?J/(kg·K)
|
|
Electrical Conductivity
|
63×106S/m
|
|
Thermal Conductivity
|
429W/(m·K)
|
Silver Powder Production Process
The silver powder production process is divided into mechanical grinding and chemical reduction processes. The chemical reduction process is able to produce higher quality and more stable batch products. Silver powder, by physical morphology, is divided into granular silver powder, spherical powder, nano silver powder, flake silver powder, etc. Different preparation processes result in different morphologies.
- Silver Nanoparticles :
Raw Materials → Chemical Reduction → Precipitation → Filtration → Drying → Crushing → Screening → Finished Product
- Spherical Silver Powder:
Melting → Atomization → Cooling → Classification → Finished Product
- Nano Silver Powder:
Solution Preparation → Reduction → Dispersion → Purification → Drying → Finished Product
- Silver Flake:
Ball Powder → Wet Milling → Washing → Drying → Finished Product
Applications of Silver Powder
Silver powder has excellent electrical conductivity, heat conductivity, and corrosion resistance and is therefore widely used in the field of electronics, the aerospace industry, the automobile industry, medical healthcare, etc.
- In the field of electronics, Ag powder is used for the manufacture of electronic components such as capacitors, resistors, inductors, etc.;
- In the aerospace industry, Ag powder is used for the manufacture of high-temperature burn-resistant materials and corrosion-resistant coatings;
- In automotive production, Ag powder is used to create batteries and catalysts;
- For medical purposes, Ag powder is used to create antibacterial materials and medical instruments.
Silver powder with various morphologies has varied application points.
Nano silver powder normally has particle sizes between 1 and 100 nanometers. It contains properties that are very different from general silver materials. Due to its extremely tiny size, the specific surface area of nano silver powder is extremely high, which indicates that nano silver powder stands out for its antibacterial and electrical conductivity. The antibacterial function of nano silver powder is widely utilized in the medical field. In addition, nano silver powder is also widely used in printed electronics, flexible circuits, etc.
Flake silver powder, characterized by its unique flake structure, occupies a vital place in the field of electrical conductivity. It finds major uses in conductive adhesives, conductive silver paste, thin-film switches, touch screen circuits, LED dispensing, etc.
