Technical Library » Plating Topics » Why are there cosmetic disclaimers on my quote for functional or matte finishes such as copper or tin/lead?

Why are there cosmetic disclaimers on my quote for functional or matte finishes such as copper or tin/lead?

Many of the finishes offered by Advanced Plating Technologies have a high degree of cosmetics associated with them.  Bright gold and lustrous nickel finishes such as bright electrolytic nickel or medium phosphorus electroless nickel are good examples of finishes that will have a higher deposit luster and more cosmetic appearance due to intrinsic depositional characteristics and the specific elements in the deposit.

Other finishes offered by Advanced Plating Technologies are functional finishes intended fur a specific engineering purpose.  Examples of these finishes include matte tin, tin/lead, lead or sulfamate nickel finishes as well copper deposits.  These finishes are intended for specific engineered purposes including soldering, brazing, babbitting, current carrying capacity or heat treat stop off.  Due to the very nature of these deposits they can be susceptible to certain cosmetic shortcomings that are generally noted on the quotation if applicable.

Some examples of cosmetic disclaimers include:

Matte Deposits such as Matte Tin, Tin/Lead or Unbrightened Nickel such as Sulfamate Nickel:

These deposits are fully matte and can have a slightly mottled appearance due to the fact that they are plated free of any organic additives to control the appearance or grain size of the deposit.  These deposits can also be very susceptible to water staining and in some cases finger printing due to the structure of the deposit.  The very reason why these finishes function well for their intended purpose are why they may have the cosmetic shortcomings listed above.  If alterations to the bath or process are made to improve cosmetics, the deposits will not perform as intended for the application.

Reactive Deposits such as Copper or Silver:  Elements such as copper and silver can react with elements in the atmosphere including sulfur bearing compounds and oxygen.  The reaction of the deposits with these elements is a thermodynamic fact that can not be altered.  These reactions can cause issues such as surface staining or discoloration and tarnishing.  The environment in which the parts stored can have a large impact on the reactions and timeframe in which the reactions can occur.  There are steps that can be taken including tarnish inhibitors and sealed nitrogen packaging which can compensate for the reactivity of the deposit.  If the appearance of reactive deposits is a concern, a representative of the technical sales group at APT can advise of inhibits or packaging methods that can help mitigate these effects.