Electroless plating properties
Chemical Resistance
NIPLATE® coatings generally have high chemical resistance in many environments. In particular, NIPLATE® 500, an electroless nickel plating with a high phosphorus content, demonstrates a higher chemical resistance than NIPLATE® 600, an electroless nickel plating with a medium phosphorus content. Consequently, it should be chosen for applications where chemical resistance is the primary requirement.
The following tables list the resistance of electroless nickel coatings to chemicals and food contact, respectively. These data have been extracted from the available literature [Gawrilov, G.G.: "Chemische (stromlose) Vernicklung", Eugen G.Leuze Verlag, Bad Salgau, 1974], [Riedel,W.: "Funktionelle Chemische Verniklung", Eugen G.Leuze Verlag, Bad Salgau, 1989].
These tables should be regarded as indicative of only the coating's environmental compatibility and do not indicate corrosion protection of the base material. The overall performance of the coated workpiece depends largely on the type and quality of the base material.
The listed data can be used for an initial material selection, but the compatibility of the NIPLATE® coatings must be verified by field testing. Variations in the contract conditions between the coating and the chemical substance can significantly change the coating's chemical resistance.
Table of the chemical resistance of electroless nickel coatings to various chemicals
Legend
- A: layer corrosion rate less than 2.5 µm/year: excellent chemical compatibility with slight or no coating corrosion.
- B: layer corrosion rate less than 12.5 µm/year: good chemical compatibility with some coating corrosion.
- C: layer corrosion rate less than 25 µm/year: poor chemical compatibility with moderate coating corrosion.
- D: layer corrosion rate greater than 25 µm/year: poor chemical compatibility with heavy coating corrosion.
| Medium | Conc. % by weight | Temp. (°C) | Aeration | Medium phosphorous Electroless Nickel Plating resistance | High phosphorous Electroless Nickel Plating resistance |
|---|---|---|---|---|---|
| Acetic acid | 5 | 20 | no | C | C–B |
| Acetic acid | 5 | 20 | yes | D | - |
| Benzoic acid | saturation | 20 | no | -- | D |
| Boric acid | saturation | 20 | no | C | C |
| Citric acid | 5 | 20 | no | A | A |
| Hydrochloric acid | pH 1.5 | 20 | no | D | D |
| Hydrochloric acid | pH 1.5 | 20 | yes | D | D |
| Chromic acid | 2–100 | 20 | no | -- | D |
| Formic acid | 88 | 20 | no | -- | B |
| Fluoroboric acid | 25 | 20 | no | -- | D |
| Malic acid | saturation | 20 | no | -- | A |
| Nitric acid | 2–100 | 20 | no | -- | D |
| Oleic acid | 100 | 20 | no | A | A |
| Oxalic acid | saturation | 20 | no | -- | A |
| Picric acid | 100 | 20 | no | -- | D |
| Hydrogen sulfide | 100 | 20 | no | -- | A |
| Sulfuric acid | 1–5 | 20 | no | D | C–D |
| Sulfurous acid | 2–60 | 20 | no | -- | D |
| Stearic acid | saturation | 20 | no | A | A |
| Fatty acids | 100 | 20 | no | -- | B |
| Demineralized water | -- | 20 | no | A | -- |
| Demineralized water | -- | 20 | yes | A | -- |
| Demineralized water | -- | 49 | no | A | -- |
| Demineralized water | -- | 80–82 | no | A | A |
| Distilled water | -- | 20 | no | A | A |
| Sea water | -- | 20 | no | -- | A |
| Aluminum chloride | saturation | 20 | no | -- | D |
| Aluminum sulfate | saturation | 20 | no | B | B |
| Ammonium chloride | saturation | 20 | no | -- | B |
| Ammonium hydroxide | 5–28 | 20 | no | -- | C |
| Ammonium nitrate | saturation | 20 | no | B | B |
| Ammonium phosphate | saturation | 20 | no | C | -- |
| Gasoline | 100 | 20 | no | A | A |
| Aviation gasoline | 100 | 20 | no | -- | A |
| Benzene | 100 | 20 | no | A | A |
| Butadiene | 100 | 25 | no | -- | A |
| Butanol | 100 | 20 | no | -- | A |
| Calcium chloride | 48.5 | 20 | no | A | A |
| Calcium hydroxide | saturation | 60 | no | -- | A |
| Calcium nitrate | saturation | 20 | no | -- | A |
| Carbon tetrachloride | 100 | 20 | no | A | A |
| Kerosene | 100 | 20 | no | -- | A |
| Chlorine | 100 | 20 | no | -- | B |
| Chlorine (dry gas) | 100 | 20 | no | A | |
| Rosin | 100 | boiling | no | -- | A |
| Diisobutyl phthalate | 100 | 20 | no | A | -- |
| Dichloroethane | 100 | 20 | no | -- | A |
| Dichloromethane | 100 | 20 | no | -- | C |
| Dimethylbenzene | 100 | 20 | no | -- | A |
| Ethanol | 100 | 20 | no | A | A |
| Ethylene | 100 | 20 | no | -- | A |
| Ethylene dichloride | 100 | 83 | no | -- | A |
| Ethylene glycol | 100 | 20 | no | -- | A |
| Phenol | saturation | 90 | no | -- | A |
| Iron(II) chloride | 100 | 20 | no | -- | D |
| Iron(II) nitrate | 100 | 20 | no | -- | D |
| Iron(II) sulfate | 100 | 20 | no | -- | D |
| Formaldehyde | 37 | 20 | no | -- | B |
| Glucose | saturation | 20 | no | A | A |
| Glycerine | 100 | 20 | no | -- | A |
| Lithium chloride | saturation | 20 | no | -- | A |
| Magnesium chloride | 2–50 | 20 | no | -- | A |
| Magnesium hydroxide | 2–100 | 20 | no | -- | A |
| Mercury chloride | saturation | 20 | no | -- | D |
| Methanol | 100 | 20 | no | A | A |
| Methyl ethyl ketone | 100 | 20 | no | -- | A |
| Nickel chloride | saturation | 20 | no | -- | C |
| Nickel sulfate | saturation | 20 | no | -- | A |
| Oleum | 20 | 20 | no | -- | D |
| Mineral oil | 100 | 20 | no | -- | A |
| Paraffin | 100 | 20 | no | -- | A |
| Tetrachloroethylene | 100 | 20 | no | -- | A |
| Petroleum | 100 | 20 | no | A | A |
| Lead acetate | saturation | 20 | no | -- | B |
| Lead nitrate | saturation | 20 | no | -- | A |
| Potassium carbonate | saturation | 20 | no | -- | A |
| Potassium chloride | saturation | 20 | no | -- | A |
| Potassium ferricyanide | saturation | 20 | no | -- | B |
| Potassium hydroxide | 2–50 | 20 | no | -- | A |
| Propane | 100 | 20 | no | -- | A |
| Copper(I) chloride | saturation | 20 | no | -- | D |
| Copper(II) nitrate | saturation | 20 | no | -- | D |
| Copper(II) sulfate | 2–30 | 20 | no | -- | C |
| Sodium bicarbonate | saturation | 20 | no | -- | B |
| Sodium borate | saturation | 20 | no | B | B |
| Sodium carbonate | saturation | 20 | no | A | B |
| Sodium chloride | saturation | 20 | no | -- | A |
| Sodium cyanide | 5 | 20 | no | C | B |
| Sodium phosphate | saturation | 20 | no | -- | A |
| Sodium hydroxide | 2–73 | 20–115 | no | A | A |
| Sodium hypophosphite | saturation | 20 | no | A | -- |
| Sodium sulfate | saturation | 20 | no | -- | A |
| Sodium sulfide | saturation | 20 | no | -- | A |
| Toluene | 100 | 95 | no | -- | A |
| Turpentine | 100 | 20 | no | -- | A |
| Trichloroethylene | 100 | 95 | no | -- | A |
| Trichloromethane | 100 | 61 | no | -- | B |
| Urea | 25 | 20 | no | A | A |
| Steam | -- | 425 | no | -- | A |
| Steam condensate | -- | 80 | no | -- | A |
| Vinyl chloride | 100 | 35 | no | -- | A |
| Zinc chloride | saturation | 20 | no | -- | B |
Table of the chemical resistance of electroless nickel coatings in contact with food
| Medium | pH | Vol. test [ml] | Duration Test [h] | Corrosion rate [µm/year] | Dissolved nickel [mg] | Daily nickel release [µg/l/day] |
|---|---|---|---|---|---|---|
| Vinegar | 2.9 | 470 | 1729 | 7.0 | 32 | 210 |
| Canned pineapple | - | 500 | 1681 | 0.3 | 0.8 | 6 |
| Chicken broth (3 tests at 95°C/203°F) | 6.0 | 200 | 312/502 | 1.0 | 2.0 | 19 |
| Coffee | 5.3 | 700 | 1729 | 9.9 | 25 | 240 |
| Coffee (4 tests at 95°C) | 4.8 | 200 | 312/554 | 4.7 | 18 | 200 |
| Cooked onions | - | 450 | 1702 | 0.8 | 1.6 | 10 |
| Mushrooms | - | 150 | 1681 | 0.6 | 3.3 | 7 |
| Gin (2 tests) | 7.5 | 150 | 3910 | 0.02 | 3.4 | 3 |
| Milk (2 tests at 2°C) | 6.4 | 950 | 1248/1633 | 0.04 | - | - |
| Buttermilk (2 tests at 2°C) | - | 950 | 1248/1633 | 0.6 | - | - |
| Lemonade | - | 950 | 1702 | 11.4 | 15 | 200 |
| Mayonnaise | 3.7 | 470 | 1681 | 0.2 | 0.9 | 6 |
| Canned corn | 6.2 | 250 | 1702 | 0.7 | 2 | 7 |
| Margarine (2°C) | - | 200 | 1,633 | - | - | - |
| Vegetable oil | - | 470 | 1729 | - | - | - |
| Spanish olives | 3.7 | 250 | 1702 | 0.3 | 1.2 | 4 |
| Tomato puree | 4.2 | 400 | 1681 | 0.5 | 2.2 | 13 |
| Canned peas | 6.1 | 450 | 1702 | 0.2 | 0.3 | 2 |
| Rum | 5.8 | 150 | 3910 | 0.2 | 10 | 9 |
| Sardines in soybean oil | - | 30 (oil) | 1681 | - | - | - |
| Sherry | 3.8 | 150 | 3910 | 6.4 | 170 | 160 |
| Lemon juice | 2.3 | 800 | 1702 | 1.0 | 1.7 | 19 |
| Apple juice | 3.1 | 850 | 1702 | 1.2 | 1.5 | 18 |
| Tomato juice (2 tests) | 4.2 | 710 | 1321/1336 | 0.5 | 0.7 | 9 |
| Grapefruit juice | 3.2 | 900 | 1702 | 0.5 | 0.6 | 8 |
| Prune juice | - | 1000 | 1702 | 1.0 | 0.1 | 1 |
| Grape juice | 4.0 | 800 | 1702 | 1.8 | 2.6 | 29 |
| Tea | 2.6 | 750 | 1729 | 4.2 | 10 | 100 |
| Tea (4 tests at 95°C) | 2.6 | 200 | 312/554 | 9.0 | 7.5 | 84 |
| Tequila (2 tests) | 4.8 | 150 | 3910 | 0.4 | 15 | 14 |
| Eggs (2 tests at 2°C) | 8.3 | 300 | 1248/1633 | 0.2 | - | - |
| Scotch whisky | 5.3 | 150 | 3910 | 1.8 | 50 | 46 |
| Bean soup | - | 500 | 1702 | 0.7 | 0.2 | 1 |
| Mushroom soup | - | 250 | 1702 | 0.3 | 0.8 | 3 |
| Tomato soup | - | 250 | 1702 | 0.5 | 1.8 | 6 |
| Vegetable soup | - | 250 | 1702 | 1.2 | 2.5 | 9 |