Steel coated with chrome plating or with nickel plating will have different hardness and looking. After coating with chrome or nickel then the surface become more interesting and stand to corrode. This is the basic purpose of steel coating. The stand to corrode and how long it can be stay on the surface depend on the dept of coating and the strength of coating material on the plate surface. One of how to test the strength of this using hardness testing. This tool work is use a fixed forced and given identifier, that show the harder of surface material.
The value of hardness test is identified by measuring the depth of the area of the surface by using several methods. One method to identify of hardness is use Rockwell hardness test method, this method is the most commonly used to test hardness of steel surface.
The standard of hardness is illustrated by the most hardest material is diamond which have hardness value of 10, other material will have below this.
Soft: scale value = 1 – 3
Medium hard: scale value = 4 – 6
Hard: scale value = 7 - 10
