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ASTM B488
Specifications

Technical Notes

Prior to requesting a quote, the purchaser needs to supply the following information to the supplier in the purchase order or other governing document

  • The name, designation, and date of issue of this specification.
  • Classification: Type, Code, and thickness (or mass per unit area)
  • Presence and thickness of underplating, if required
  • Significant surfaces must be specified
  • Requirement, if any, for performance testing such as porosity testing, solderability testing, ductility testing etc.
  • If the substrate is one that requires a nickel underplating
  • Whether or not stress relief has been or is to be done, whether embrittlement relief bake is to be done (steel parts only).
  • Sampling plan employed.

Coating Class is the coating thickness in micrometers. Ex: Class 0.25 has a coating thickness of 0.25um.

Type

Type represents the percentage of the plating is pure gold:

  • Type I = 99.7% pure gold.
    For general-purpose, high-reliability electrical contacts, and wire wrap connections.
  • Type II = 99% pure gold.
    General-Purpose Wear Resistant Gold — Will not withstand high-temperature applications because the hardening agents in the gold coating will oxidize.
  • Type III = 99.9% pure gold.
    Code A Gold—For semiconductor components, nuclear engineering, thermocompression bonding, thermosonic bonding, ultrasonic bonding, solderability, and high-temperature applications

Knoop Hardness Range ASTM Code MIL-DTL-45204 Grade
90HK maximum A A
91-129 HK B B
130-200 HK C C
>200 HK D D

Nickel Underplating—For thickness Classes except 5.0, a nickel underplating shall be applied before the gold coating when the product is made from copper or copper alloy.
Strikes—It is recommended to apply a gold strike to the underplate or substrate, except if the latter is silver or platinum, prior to applying the gold top coating.

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Services & Capabilities

Electroplating
Anodizing
Passivation
Plating Substrates
Pre- & Post-Process Treatments
Dedicated Outsourced Finishing
electroplating-1

Electroplating

Electroplating

Electroplating is a process by which one metal is deposited onto a base metal (substrate). These deposited metals offer a variety of benefits including thermal and electrical conductivity, corrosion resistance and more. AOTCO electroplates a wide variety of both standard and exotic metals.

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Anodizing

Anodizing

Sometimes called a “conversion coating” Anodizing is an electrolytic process in which an oxide (anodic) layer is chemically built on the surface of the substrate material, providing anti-corrosion and other benefits. AOTCO offers, Type I, Type 2, Type 3 and Titanium anodizing services.

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Passivation

Passivation

Passivation is a term for a variety if processes that make a metal (most commonly stainless steel) or other substance unreactive, or passive, by altering the surface layer or coating the surface with a thin inert layer. AOTCO performs both citric and black oxide passivation techniques to a range of specifications.

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Beryllium

Plating Substrates

Plating Substrates

AOTCO plates on a wide variety of Common, Exotic and Non-Metallic substrates, bringing exceptional expertise to magnesium, titanium, beryllium, BeCu, TeCu, tungsten and more. In some cases we pass as high as 450 degrees celsius, allowing for high temperature soldering, brazing, or post machining operations after plating.

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Pre- & Post-Process Treatments

Pre- & Post-Process Treatments

Pre-Process: In addition to offering both mechanical & chemical cleaning options, AOTCO specializes in creating solutions for complicated, difficult and tight-tolerance masking challenges. Post-Process: For clients with specialized needs AOTCO offers laser marking and engraving options, including color change caused by chemical or molecular changes, charring, foaming, melting, ablation, and more.

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Dedicated Outsourced Finishing

Dedicated Outsourced Finishing

Part of our cornerstone goal of building long-term, collaborative & solution-oriented partnerships, AOTCO will devote reserved physical and human resource capacity for our clients with long-term finishing and deadline requirements. For these partnerships our commitment is that AOTCO manages the process, while YOU control the results.

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