Answer:
Reaction bonded Silicon carbide: 2500-3500 HV
Tungsten carbide: 1800-2500 HV.
316 Stainless Steel: 152 HV
Mild steel: 130 HV
Step-by-step explanation:
In order to list those seal face materials by hardness, we look up what are the values of hardness for each material in a hardness scale.
We are going to use Vickers scale, an indentation method of measuring hardness, it measures the deformation left in a sample by a constant compression load from an indenter (a diamond pyramid) with an adequate (to the material) force, as the result is independent from the test force.
1. Reaction bonded Silicon carbide: 2500-3500 HV
2. Tungsten carbide: 1800-2500 HV
3. 316 Stainless Steel: 152 HV
4. Mild steel: 130 HV