The authoritative public forum
  for Metal Finishing since 1989
  

  -----

500 hour salt spray resistance with electroless nickel plating

I am trying to get information on a 500 hour electroless nickel coating on aluminum. It needs to pass a 500 hour salt spray test. We our now using an old Shipley process from DuPont, Duroplate 84, with an enhancer. This gives us a 100 hours. What companies sell process and or chemicals that are more up to date? I have heard that the Shipley process is quite old.

John Elverum
- Paso Robles, California
1999

---

We discourage people from claiming that a particular product is not good or another is better. With the anonymity of the web it is not practical to determine vested interests.

But when you are finished with your investigation of the various processes I predict that you will find that the condition of the substrate and the thickness of the nickel coating will be far more critical factors than the brand name of the process. Please see letters 381 and 572.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

---

Hi John, the corrosion protection of Electroless Nickel depends upon the coating being "pore free" and depending upon the alloy of Aluminium you are plating and the degree of pretreatment you are applying, you may be enhancing the pores produced by etching. Explain your total process in more depth and I reckon we could all give you some advice. Regards

John Tenison - Woods
- Victoria Australia
1999

---

What kind of EN are you using? High, mid or low Phosphor? The only kind that can give 500 hours in NSS is the high phosphor EN.

But, you need at least 25 microns of EN.

All that is true for flat parts. Parts with Complicated shapes sometimes react differently.

It also depends on the surface; if it is rough, results may not be so good. In case you put your parts in the oven to improve hardness, you destroy its ability to withstand NSS.

Sara Michaeli
Tel-Aviv-Yafo, Israel
1999