Circa 1975 60u in. was used on gold cerdip packages. During the first gold price run up they scrambled to gather scrap to make a quarters revenue. The gold price spike coincided with business tanking, funny that.
Porosity is problematic with coatings this thin. Most have to do with specifics of manufacturing; the advantage of plating to spec (among other things) forces discipline over process control and technique.
Substrate surface roughness plays a key role in determining the degree of porosity in the final coating, along with the specific plating chemistry. Micro smoothness and lack of features (asperities) before plating goes a long way to reducing porosity.
Electropolishing, using self-leveling nickel undercoats or other high cost pretreatments can greatly reduce the thickness needed to minimize coating porosity failures, but these are usually one-off answers not amenable to mass production.
Usually, given the lack of rigor at even the best commercial houses, 1.5 microns is insufficient thickness to realistically increase mtbf. Another technique is using at least 2 different deposition chemistries during plating, but this again is pricey and time consuming.
It's hard and very corrosion resistant, which makes it great for certain needs. I'm sure it's a PITA to plate successfully, however. It's also not_cheap. Surprised more things aren't moving to Pt or Pd given Au's bulk price right now. Been a while since I looked at all the noble metal electroplating chemistries (all of which made me quickly go "nope!" to bringing in-house, we don't have the expertise)
But adding my huge thanks to AuPlater's posts, albeit the Au part seems to be an undersell.
But adding my huge thanks to AuPlater's posts, albeit the Au part seems to be an undersell.
I am building a rocket in my garden, in order to board with some friends to the moon.
I take advantage of the presence of so many EE101 graduated experts here to ask 3 questions:
- What weld should I use for the components of my navigation system ?
(The round trip will only last a few days.)
- The presence of this layer of Rhodium under the thin layer of gold on my printed boards may-it affect the intelligibility of communications with the control room ?
- Is the presence of pieces of hair cut in 1000 likely to cause malfunctions with the connectors?
I take advantage of the presence of so many EE101 graduated experts here to ask 3 questions:
- What weld should I use for the components of my navigation system ?
(The round trip will only last a few days.)
- The presence of this layer of Rhodium under the thin layer of gold on my printed boards may-it affect the intelligibility of communications with the control room ?
- Is the presence of pieces of hair cut in 1000 likely to cause malfunctions with the connectors?
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Rhodium... looks great on paper... ~ 1/2 the density of gold, platinum, iridium... one of the lighter noble metals, so when plated goes twice as far per unit area. Still very expensive, tho, often quite a bit higher than gold.
Way back in the 1960's Ted Kozul & Baytron set the standard for high quality commercial microwave waveguides, couplers, circulators, and such, made from silver with a rhodium flash to stop corrosion. These components are still being used around the world, and had a robust, almost gem like quality to them. Niche market.
Problem is, rhodium is difficult to dissolve in most anything, so producing and controlling a usable electrolyte to plate from is difficult. Because of its high cost, not much demand for coatings thicker than 1/4 micron or so exist (mainly jewelry as a coating over white gold) so low concentration flash coatings were about all that existed. Plus the baths tended to be unstable, and the coatings got rough and grainy at any appreciable thickness.
Bottom line, unless needed for hardness or appearance, gold deposition was / is cheaper, more versatile, and can be deposited with many different properties optimized for its use. The rhodium craze (in the audio industry) was a marketing tool to raise the sell point of whatever was being coated
Rhodium... looks great on paper... ~ 1/2 the density of gold, platinum, iridium... one of the lighter noble metals, so when plated goes twice as far per unit area. Still very expensive, tho, often quite a bit higher than gold.
Way back in the 1960's Ted Kozul & Baytron set the standard for high quality commercial microwave waveguides, couplers, circulators, and such, made from silver with a rhodium flash to stop corrosion. These components are still being used around the world, and had a robust, almost gem like quality to them. Niche market.
Problem is, rhodium is difficult to dissolve in most anything, so producing and controlling a usable electrolyte to plate from is difficult. Because of its high cost, not much demand for coatings thicker than 1/4 micron or so exist (mainly jewelry as a coating over white gold) so low concentration flash coatings were about all that existed. Plus the baths tended to be unstable, and the coatings got rough and grainy at any appreciable thickness.
Bottom line, unless needed for hardness or appearance, gold deposition was / is cheaper, more versatile, and can be deposited with many different properties optimized for its use. The rhodium craze (in the audio industry) was a marketing tool to raise the sell point of whatever was being coated
I'm sure I did see Osmium plated connectors once in the 80s but that may be memory playing tricks with me.
Back in the 90s there was a change in the plating of some RF connectors for low frequency (Coupla GHz levels). Silver plate was causing corrosion problems in the field and the iron content in some nickel plate was causing IMD issues. The suppliers came up with a new formulation with usual trade names but I think were related to the class of Cu-Sn-Zn plating that is often called white bronze and comes with some great names like 'Optalloy'. It was shiny, hard enough for our needs, corrosion resistant and gave the IMD performance we needed. Never seems to have done the crossover into audio. I guess because actual performance doesn't really matter
Back in the 90s there was a change in the plating of some RF connectors for low frequency (Coupla GHz levels). Silver plate was causing corrosion problems in the field and the iron content in some nickel plate was causing IMD issues. The suppliers came up with a new formulation with usual trade names but I think were related to the class of Cu-Sn-Zn plating that is often called white bronze and comes with some great names like 'Optalloy'. It was shiny, hard enough for our needs, corrosion resistant and gave the IMD performance we needed. Never seems to have done the crossover into audio. I guess because actual performance doesn't really matter
If the moon is made of Wensleydale possibly mars is made of Red Leicester. Please tell us when you find out.
After 2 or 3 glasses of an old GLENDRONACH, everything is RoHS compliant.Is he RoHS compliant...?
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