MIL-DTL-45204D
TABLE VII. Modification in procedure for test method ASTM B487
Step in ASTM B487
Modification
Selection of section for test
Use a right angle cross section or longitudinal section.
Plate the articles with a coating at least 0.001 inches thick
of copper, nickel, or iron to protect the edges during
Preparation of specimens
grinding and polishing. The first layer or overplate shall
be a copper strike deposited from a cyanide solution
followed by the relatively thick overplate.
Grind and polish, following the instructions for polishing
Preparation of section
zinc, cadmium, tin, and lead coatings.
Use an etching solution so as to obtain the maximum
contrast between the coating and the adjacent metals.
Etching
Obtain such contrast by etching either the coating or the
adjacent metal by an appropriate reagent.
Using the metallographic microscope and a magnification
Procedure,
of at least 1000 diameters, take a minimum of five (5)
Use of microscope
measurements at random locations on each specimen.
Measurements shall be expressed to five (5) decimal places
(0.00001 inches).
4.6.2 Adhesion tests. Adhesion of test specimens shall be performed at room temperature by
means of the bend test (see 4.6.2.1) unless the plated articles are not readily adaptable. When not
readily adaptable to the bend test, adhesion of the plated articles shall be determined by means of
the cutting test or by the baking test.
4.6.2.1 Bend test. Plated articles shall be bent repeatedly through an angle of 180° on a diameter
equal to the thickness of the specimen until fracture of the basis metal occurs. No detachment of
the coating shall be possible by probing with a sharp instrument. Cracks in the basis metal or
plating shall not be considered failure unless accompanied by flaking, peeling or blistering.
Examination shall be at four (4) diameter magnification.
4.6.2.2 Cutting test. The adhesion of plated articles shall be determined by cutting the plating
from the basis metal at the interface(s) with a sharp instrument. The specimens shall be visually
examined at four (4) diameter magnification to determine whether removal has been caused by
cutting away of an adherent plate or lifting of a non-adherent plate.
4.6.2.3 Baking Test. The adhesion shall be determined by heating the plated articles at 250° to
300° F for one (1) hour. After removal and cooling, the surface of the articles shall be examined
at four (4) diameter magnifications for any evidence of flaking, peeling or blistering.
10
For Parts Inquires call Parts Hangar, Inc (727) 493-0744
© Copyright 2015 Integrated Publishing, Inc.
A Service Disabled Veteran Owned Small Business