Different Materials for Seal Faces: Hardness Comparison
What are the hardness levels of various seal face materials?
List the following seal face materials in order of hardness. i.e Hardest first, softest last.
(a) 316 Stainless Steel
(b) Mild steel
(c) Reaction bonded Silicon carbide
(d) Tungsten carbide
Answer:
Reaction bonded Silicon carbide: 2500-3500 HV
Tungsten carbide: 1800-2500 HV
316 Stainless Steel: 152 HV
Mild steel: 130 HV
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