ASTM B607-15

1.1 Nickel boron coatings are produced by autocatalytic (electroless) deposition from aqueous solutions. These solutions contain either an alkylamineborane or sodium borohydride as a reducing agent, a source of nickel ions, a buffer, complexant, and control chemicals.

1.2 This specification describes the requirements for coatings of autocatalytic nickel boron deposited from aqueous solutions onto substrates for engineering use. The specification classifies these coatings into two types:

1.3 The coatings are hard and uniform in thickness, even on irregular shaped parts, and used in a wide range of applications.

1.4 Process solutions formulated with an alkylamineborane usually produce coatings that contain 0.1 to 3.5 % boron. Thin coatings of this type provide bondability and solderability on electronic components such as lead frames, electrical contacts, and headers. To maintain solderability, these coatings are generally not heat treated.

1.5 Process solutions formulated with sodium borohydride are strongly alkaline and are frequently used to plate steel and titanium parts to impart surface hardness and wear resistance properties. Deposits produced from these processes can contain 3 to 5 % boron and thallium or other metals which are used to stabilize the plating solution and modify the coating properties.