FOR TOP PERFORMANCE, CHOOSE CLEAN
When sourcing raw material for punches and dies, as long as you choose the right grade steel, you should be good, right? Not quite. Steel grade is an important part of the equation, but a major influence on tool performance is steel cleanliness.
WHAT DOES AN AISI/SAE STEEL GRADE MEAN?
Standard steel grades, as determined by the American Iron & Steel Institute (AISI) and Society of Automotive Engineers (SAE) or the International Organization for Standardization (ISO), indicate how much of each element is present in given steel.
The AISI/SAE steel designation system uses a four digit code to characterize the chemical composition of the steel. Today, steel grades are typically designated using SAE followed by a four digit number. The first two digits refer to the material type and concentration and the last two digits indicate the carbon concentration to 0.01 percent.
For example, a chromium steel with a grade of 5130 is 1% chromium and a minimum of 0.30% carbon. A Manganese steel with a grade of 13xx contains 1.75% Manganese.
And while the grade gives us vital information about the steel’s composition, it doesn’t clue us into the steel’s hardness, cleanliness or grain structure. And it’s the latter qualities that are key to the steel’s performance.
WHY CHOOSE CLEAN STEEL?
Clean steel is stronger, can be polished to a higher finish, wears better, and its mirror finish lasts longer than dirty steel. Cleanliness impacts crucial properties of steel such as corrosion resistance, toughness and fatigue. Thus, the dirtier the steel, the shorter the tool life.
Cleanliness refers to how many inclusions, or air gaps, and contaminants, such as sulfides, are in the steel. ASTM International sets standard test methods used by the steel industry as well as many other industries to ensure consistency and quality. Specifically, the steel industry follows a cleanliness rating system called ASTM E45 to determine the inclusion content of steel. The lower the number, the better the cleanliness of the steel.
So what causes “dirty” steel? There are two types of inclusions that impact steel cleanliness. Micro inclusions are caused by chemical or physical reactions that occur during melting and solidification – this can include air gaps or chemicals that remain after oxidation. Macro inclusions are the result of external debris or material that makes its way into the steel during processing. The higher the inclusion content, the dirtier the steel.
Wilson Tool understands the impact of clean steel on tool performance, which is why we follow a cleanliness standard that meets or exceeds the industry norms. This means that customers like you can be sure the steel we use for our tooling will last longer and produce a higher quality product.
In the case of tablet tooling, choosing a cleaner tool steel not only dramatically increases tool life but improves performance by minimizing common challenges such as sticking, picking and fracture.
To learn more about clean steel and the technical advantages of working with Wilson Tool, contact our tooling technicians at firstname.lastname@example.org or 800-467-8444.