Cortland, Thanks for your information. A few questions/points of clearification if I might. The sucess of thin layers of gold or Pd will depend on the roughness of the substrate(Al in this case), porosity of Au, pressure and corrosion potential of the mating element to the Au and what tests are done for qualification , i.e. D.C. resistance across the interfaces, X/Au/Al. Another important face would be is the system open to fretting and crevice corrosion and what environments, i.e. Chloride-Au will not work.
Thanks Richard Haynes 609-497-4584 -----Original Message----- From: Cortland Richmond <[email protected]> To: Richard Haynes <[email protected]>; ieee pstc list <[email protected]> List-Post: [email protected] Date: Wednesday, December 02, 1998 2:06 AM Subject: Re: Coatings that affect EMC performance >About ten years ago I had to write a critical features list on a piece of >equipment that used yellow chromate over aluminum. It turned out not to be >too difficult; silver was too little, yellow and brown were too much and >"waay" too much respectively. Only a light gold tint was correct. > >Holding the vendor to that,on the other hand... > >Cortland > >====================== Original Message Follows ==================== > > >> Date: 30-Nov-98 21:27:31 MsgID: 1065-66891 ToID: 72146,373 >From: "Richard Haynes" >INTERNET:[email protected] >Subj: Re: Coatings that affect EMC performance >Chrg: $0.00 Imp: Norm Sens: Std Receipt: No Parts: 1 > > >Don, >The "yellow..." could mean a yellow chromate film(coating) on aluminum >metal(for example) applied for corrosion protection. The advice not to used >is because of the high impedance. The film EMC people use is clear because >of the low impedance. For yellow, purple, etc there is good corrosion >resistance whereas the clear coating is low corrosion resistance but also >low Z). So we have the compromise between low Z and low corrosion >resistance >or high Z and high corrosion resistance. There are also porosity of the >film >with processing conditions. > >This is my best guess with the information available. > >Be glad to help you on more specifics. > >Richard Haynes >609-497-4584 > >-----Original Message----- >From: UMBDENSTOCK, DON <[email protected]> >To: 'EMC-PSTC Discussion Group' <[email protected]> >Date: Monday, November 30, 1998 6:06 PM >Subject: Coatings that affect EMC performance > > >>Hello Group, >> >>I remember recently (within the last quarter?) reading a thread about >>different coatings, one of which everyone said "don't use". I have >searched >>through the RCIC "Recent Threads" and could not find a related subject. >Can >>anyone steer me to that thread? (something about "yellow ____"?) >> >>Regards, >> >>Don Umbdenstock >>Sensormatic >> >>--------- >>This message is coming from the emc-pstc discussion list. >>To cancel your subscription, send mail to [email protected] >>with the single line: "unsubscribe emc-pstc" (without the >>quotes). For help, send mail to [email protected], >>[email protected], [email protected], or >>[email protected] (the list administrators). >> >> > > >--------- >This message is coming from the emc-pstc discussion list. >To cancel your subscription, send mail to [email protected] >with the single line: "unsubscribe emc-pstc" (without the >quotes). For help, send mail to [email protected], >[email protected], [email protected], or >[email protected] (the list administrators). > >====================== End of Original Message ===================== > --------- This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to [email protected] with the single line: "unsubscribe emc-pstc" (without the quotes). For help, send mail to [email protected], [email protected], [email protected], or [email protected] (the list administrators).
