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Pure Silver

 Interner LinkGERMAN HIGHEND Silver Cable is made of pure polycrystalline silver.

The state of the art GH-products are of the laboriously made
long crystalline pure silver !!

The silver is typically 99.995% pure (4-5N).
This means that it contains impurities of 50-80mg per kilogram of silver.
Of this 50-80mg impurity, 40-50mg is copper. (1 kilogram = 1,000,000mg)

Under a high definition microscope is it apparent where the benefit
of this precious metal lays: the large silver crystals provide a low
resistance and reduce the distortion created at the crystal boundaries.

A few photos of magnified material cross-sections (150x)

Polycrystalline silver (PSS-Series)
Long crystal silver (LGS-Series)
OFC – LGC copper

Conductivity of Metals

Typical Values (25 degrees celcius). Typical less than 106 S/m:

· Silver: 62 · 106 S/m
· Copper: 58 · 106 S/m
· Gold: 45,2 · 106 S/m
· Aluminum: 37,7 · 106 S/m
· Brass: 15,5 · 106 S/m
· Iron: 9,93 · 106 S/m
· Chrome: 7,74 · 106 S/m
· Stainless steel (1.4301): 1,36 · 106 S/m

Silver has the highest conductivity of all metals.

 

Some manufacturers advertise with unrealistic metallurgic purities or even proclaim an absolute mono-crystalline structure of their products. Whoever spends a little time learning about metallurgy soon discovers that such claims must have derived from fantasies within the marketing departments and have nothing whatsoever to do with reality. A “8N” copper or silver is stuff for amusing fiction. Presently, the manufacture of oxygen-free conductors is for all practical purposes impossible on a commercial scale to realize!

Externer Link Here is an amusing example (in German)


        

How does one distinguish the conductivity (signal transfer) qualities of pure metals?


The conductivity of metals is determined under two parameters:
Either by temperature-dependent or temperature-independent models. The temperature-dependent model demonstrates that conductivity reduces when the temperature is lowered. The electric conductivity resistance increases when this occurs. The temperature-independent parameter model must be particularly qualified due to various factors: For example, purity, and lattice defects (foreign atoms, crystal imperfection, transfers, grain boundaries, secondary phases), need specific clarification. The conductivity is reduced by such factors. For illustrative examples here, copper (Atomic Number: # 29) and silver (# 47) in pure forms, and copper and silver with an alloy portions of 1-2% models are presented.

-As pure metal, copper has a conductance of 58 • 106 A (V • m).
-Silver has a conductance of 62 • 106 A (V • m).

If one alloys copper with 1-2% foreign atoms of, e.g., nickel (# 28), cobalt (# 27), iron (# 26), zinc (# 30), gallium (# 31), germanium (# 32) or arsenic (# 33), an increase of the electrical resistance is the consequence. The same effect can be recognized with an alloy of silver with 1-2% of, e.g., palladium (# 46), rhodium (# 45), cadmium (# 48), Indium (# 49), tin (# 50) or antimony (# 51).

Typically, the following rule applies for the increased resistance in conductivity: The resistance rises more highly depending upon the greater the difference between the atomic number and the foreign atoms to the host lattice atoms. Host lattice atoms in the models presented here are copper or silver. Foreign atoms are the alloy metal portion of 1-2%.

 

Increase in resistance by adding foreign atoms (alloy) - on the left is copper (Cu),
on the right is silver (Ag). Concentration of foreign atoms is 1%.

Thus, generally, we derive that alloys conduct current more poorly than pure metals do. To make a better high-quality conductor such as copper or silver, these must be as pure as possible. Foreign atoms in the host lattice are pollutants, whether 1% silver portion are contained in the copper (although silver is the something better, the atomic number difference is still 18!), or, as in descriptions of some [high fidelity cable] manufacturers boast, "1% gold portion in the silver," (atomic number difference 32). In pure form, copper and silver will always be the better electrical conductor. An advantage of such alloys can be partly the higher mechanical elasticity, but surely not the negative influence on the audio frequency signal!

Theoretical physics is clearly comprehensible in real-life listening sessions - you can hear the difference pure metals offer (please note: for meaningful comparisons, one must allow for long break-in periods to properly assess the benefits of pure metals!).

 

 

General information about silver

Silver has been known of since ancient times. Silver is soft and pliable with a characteristic sheen. It has the highest thermal value and conductivity of all metals. Silver is found usually in free form or in sulphuric and/or arsenic ores.   From these ores it can be extracted by cyanide complex in water solution with zinc to win it (become) as metal. The pure metal is stabile in water and oxygen however the elements in the air containing sulphur are responsible for the tarnish, typical black coating consisting of silver sulphides. Silver dissolves in hydrochloric and sulphuric acids. Some silver compounds are sensitive to light (e.g.: AgI, AgCl, AgBr), and therefore vital to photography.

Other predominant usages for silver are jewelery (pure form and alloy), electronics industry (e.g., production of contacts and conductors), and silver plating glass. 

 

Atomi characteristics

Indicated valences  1, 2

Atomic weight ( amu )    107,8682

Atomic radius - Goldschmidt ( Nm )  0,144

Electronic structure         Kr 4d10 5s1

Ionisation potential       No.  eV

1          7,58                

2          21,5                

3          34,8                

Crystal structure cubically face-centered

Natural isotopic distribution Mass number of %  

107      51,83              

109      48,17              

Ordinal number   47       

Photoelectric electron affinity ( eV )  4,7

Thermal neutron absorption cross section  (Barns)  63,8

 

Electrical characteristics

Temperature coefficient ( K-1 )  0,0041 bei 0-100C

Electrical resistance ( µOhmcm )   1,63 bei 20C

Thermal EMK opposite Pt (cold 0C hot 100C) ( mV ) +0,74

 

 

Mechanical characteristics

Material condition  soft - hard - polycrystalline

Elastic module in the traction test ( GPa )   82,7

Hardness - Vickers            25        95

Notched-bar impact-strength after Izod ( J m-1 ) 5

Bulk modulus ( GPa )      103,6

Poisson constant            0,367

Tensile strength ( MPa )   172      330

                                              

Physical characteristics

Density ( g cm-3 )     10,5 at 20C

Fusion point ( C )      961,9

Boiling point ( C )     2212

 

Thermal characteristics

Latent heat of fusion ( J g-1 ) 103

Latent heat of vaporization ( J g-1 ) 2390

Linear heat expansion coefficient ( x10-6 K-1 ) 19,1 bei 0-100C

Specific warmth ( J K-1 kg-1 ) 237 bei 25C

Heat conductivity ( W m-1 K-1 ) 429 bei 0-100C

 


Letzte Änderung: 26. Apr. 2013, © German Highend