Why Conduct a Hardness Test?
To Establish a Material heat treatment condition.
A steel ball (Brinell Hardness) or diamond prism (Vickers & Rockwell testing) is used to make an indent in the material. Based on the degree of indentation, we are able to quantify the hardness of the material
How can it help you?
Steels will have different hardness measurements depending on the its heat treatment condition. A normalised steel has been slow cooled from high temperature and has low hardness, but can be easily welded. A steel that has been cooled quickely from high temperature and then tempered will have a higher hardness and greater strength, and can be used for heavey duty shaft applications. A hardness test can tell us what heat treatment condition the material is in.
The One Eighty Engineering Solution.
A glass bottle manufacturer could not explain why their cast iron moulds did not last as long as they expected, causing the cost of bottle manufacture to increase unacceptably. By conducting a hardness test we were able to show that the material did in fact have sufficient hardness and that other root causes should be investigated. Consequently, the problem could be solved, allowing the life cycle of the moulds to increase.
The cam on a diesel engine onbiard a fishing vessel failed prematurely. Hardness testes were conducted on a section through the failed surface. We found that the case hardened depth was insufficient, which led to premature failure of the cam.
|
