Coating Measurement
Hardness and thickness are important dimensions of plating materials because the effectiveness, longevity, and cost of the final product depend, not only on the appropriate selection of coating material, but also on the amount applied, and the final surface texture, therefore there are several methods to test the properties of parts such as following:
- Hardness
- Rockwell
- Brinell
- Vickers
- Microhardness (Knoop)
- Thickness
- X-Ray fluorescence
- Eddy-current
- Magnetic induction
- Beta backscatter
Hardness is the property of a material that enables it to resist deformation, however, is not an intrinsic material property dictated by precise definitions in terms of fundamental units of mass, length, and time. A hardness property value is the result of a defined measurement procedure. Hardness tests characterize the materials and determine if they are suitable for their intended use. All of the hardness tests described in this section involve the use of a specifically shaped indenter, significantly harder than the test sample. The indenter is pressed into the surface of the sample using a specific force. Either the depth or size of the indent is measured to determine a hardness value. Four major hardness scales described are the following:
Coatings applied to base materials provide properties not inherent in the base, including corrosion and wear resistance, conductivity, color, and solderability. The amount of coating applied to a material, that is, the coating thickness, is crucial to the product's final use and cost. This section describes four non-destructive methods of measuring coating thickness. Each method was devised to achieve cost-effective, accurate, and repeatable results, and is particularly suited to a specific coating(s)/substrate combination.
The four methods described are: