There are many diferent materials available for seal faces. 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

Reaction bonded Silicon carbide: 2500-3500 HV

Tungsten carbide: 1800-2500 HV.

316 Stainless Steel: 152 HV

Mild steel: 130 HV

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