Manufacturers use a steel hardness chart to determine what type of steel should be used for different applications. The steel hardness chart is also used in conjunction with the Rockwell hardness chart.
In knife applications, different types of steel are used to provide customers with a durable material for their needs. For example, 17-7 PH is a corrosion-resistant material that is typically used in aquatic environments. The 154 CM primary material is another commonly used steel option for knives that is affordable and easy to resharpen. Many of the same properties found in the steel in these knives are applied to other steel systems for different industries.