Frank,
This is what I found:

“Brenner and Riddell (2) discovered that autocatalytic nickel plating would proceed on an immersed catalytic substrate at temperatures near 90" C in the pH range of 4 to 6. Plating was shown to occur over a wide range of nickel and hypophosphite concentrations-3 to 100 g/L (0.05 to 1.7M) for nickel and 10 to 100 g/L (0.09 to 0.94M) for hypophosphite. Under these conditions, the authors found that nickel deposition would occur on a suitable substrate without the simultaneous random reduction of nickel throughout the plating solution.”

The reference site  is 
http://www.tau.ac.il/~chemlaba/Files/Electroless/12777_02.pdf

But even with good concentration range, if pH is too low the deposition rate of P will be too high.

Regards,
Bev



Sent from Mail for Windows 10

From: Frank Kimmey
Sent: Monday, January 29, 2018 10:45 AM
To: [log in to unmask]
Subject: [TN] Phosphorus content in Electroless Nickel

Hey FAB Guys (or Chemical types or anyone else who might help),
What should the P content in the Electroless Nickel bath be?
I am concerned some of our suppliers are running to high.
This could be the cause of some Brittle Fracture failures I have been seeing.
What would you consider a good range for Phosphorus percentage in the Electroless Nickel bath?
Thanks,
FNK

Frank N Kimmey CID+
Electrical Engineer / PCB Design
VeriFone Inc
1400 W Stanford Ranch Road, Suite 200
Rocklin, CA 95765 USA
W: 1-916-625-1818
M: 1-916-833-9877
[log in to unmask]

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