Hanyang University MODERN ANTENNA HANDBOOK by CONSTANTINE A
Hanyang University MODERN ANTENNA HANDBOOK by CONSTANTINE A. BALANIS ch. 3. 5 - 3. 5. 3 Jeong Gu Ho 1/15 Antennas & RF Devices Lab.
Hanyang University Contents 3. 5 Fabrication 3. 5. 1 Materials 3. 5. 1. 1 Aluminum alloy 3. 5. 1. 2 Copper alloys 3. 5. 1. 3 Brass Alloys 3. 5. 2 Coatings and surface treatments 3. 5. 3 Corrosion 2/12
Hanyang University <anechoic chamber> Network analyzer Antenna Scanner, Motion control box 3/12 Computer control
Hanyang University <anechoic chamber> >>Provides data accuracy and validity 4/12
Hanyang University <anechoic chamber> <dipole antenna> <monopole antenna> <horn antenna> <patch antenna> <loop antenna> 5/12
Hanyang University 3. 5 Fabrication 3. 5. 1 Materials – Materials for fabrication of aperture antennas are typically metals, with occasional use of dielectrics. – Metals used are typically alloys of aluminum or copper. – Fabrication data for specialized materials is best sought from the manufacturer, but some general properties of common materials that find regular use in aperture antennas are given. 3. 5. 1. 1 Aluminum Alloys Some alloys can be strengthened and hardened by heat-treatment processes, while others can have their physical properties controlled by mechanical work-hardening processes such as rolling or forging. Aluminum alloys exist two categories (wrought alloys, casting alloys) 6/12
Hanyang University <Wrought alloys> Classification Property 5005 -H 34 A low strength non-heat treatable aluminum-magnesium. Excellent corrosion resistance. Readily formed, welded, and brazed. 5083 -H 112 5083 -H 116 5083 -H 32 5083 -H 34 A moderate strength non-heat treatable aluminummagnesium. Readily machined and welded 6061 -T 651 A moderate strength heat-treatable aluminum-magnesiumsilicon alloy. Very readily machined welded, and brazed with very good corrosion resistance. 7075 -T 651 A very high strength heat-treatable aluminum-magnesiumzinc alloy. Machinable but not readily weldable. 7/12
Hanyang University <Casting alloys> Classification Property Alloys 356 and A 356 An excellent general-purpose heat-treatable aluminumsilicon alloy for sand castings. Castings are readily weldable and have excellent corrosion resistance and good machinability. Alloys 360 and A 360 Good corrosion resistance and reasonably machinable with carbide tools Alloys 413 and A 413 Very good corrosion resistance and reasonably machinable with carbide tools. 8/12
Hanyang University 3. 5. 1. 2 copper alloys Classification Property UNS C 11000 General-purpose engineering copper Very readily formed, soldered, and brazed UNS C 10100 UNS C 10200 Essentially pure copper with improved electrical conductivity compared to UNS C 11000. Very readily formed solded, brazed and welded UNS C 14500 UNS C 14700 Improve machinability. Much more readily machined than UNS C 11000 and UNS C 10100/10200 3. 5. 1. 3 Brass alloys Classification UNS C 36000 UNS C 38500 Property Readily formed and soldered. Good corrosion resistance. 9/12
Hanyang University 3. 5. 2 Coatings and surface treatments Coatings and surface treatment can be used to enhance some property or aspect of performance. Classification Property Plating Common applications are the coatings of precious metals such as gold and silver to improve surface conductivity and/or minimize the potential for corrosion. Chemical conversion coatings Chromate conversion coatings are highly corrosion resistant, electrically conductive Passivation An existing surface or surface layer is chemically cleaned or decontaminated to make it more inert. 10/12
Hanyang University 3. 5. 3 Corrosion – Most metals are subject to corrosion in certain circumstances and this should be considered in the design. – Such as copper and aluminum alloys are quite corrosion resistant by themselves. – And may be made even more so by the surface treatment processes coatings and surface treatments. – After assembling treatment such as paint may be applied to help protect the assembly from environmental conditions that may promote corrosion. 11/12
Hanyang University Thank you for your attention 12/15 Antennas & RF Devices Lab.
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