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AUSTENITIC - Refers to 300 series stainless, the most popular of stainless alloys accounting for 85-90% of stainless fasteners sold. Named for Sir Robert Williams Austen, an English metallurgist, austenitic steel is a crystal structure formed by heating steel, chromium, and nickel to a high temperature where it forms the characteristics of 300 series stainless steel. An AUSTENITE is a molecular structure where 8 atoms of iron surround one atom of carbon, thus limiting the corrosive effects of the carbon. Austenitic fasteners give high level of corrosion resistance in the stainless family, cannot be hardened by heat treatment, and are almost always non magnetic. Sometimes heat and friction in cold forming can cause austenitic stainless to take slight magnetism, but the corrosion resistant properties remains the same. Most commonly used grade is termed as 304. Typical industries using these fasteners include: food, dairy, wine, chemical, pulp and paper, pharmaceutical, boating, swimming pool, pollution control, electronic, medical and hospital equipment, computer, textiles.

Type 316 stainless has added nickel and added molybdenum. The molybdenum (called moly) increases corrosion resistance to chlorides and sulfates, including sulfurous acids in pulp industry. It has superior tensile strength at high temperatures compared to 304. Besides pulp and paper, typical industries using 316 are: photographic and other chemicals, ink, textile, bleach, rubber.

CARBIDE PRECIPITATION - Carbon that breaks loose from its bond within the stainless solution when material is heated between 800-1400 degrees. Under severe corrosive conditions, it can result in extra oxidation and surface corrosion.

CARBON - Adds strength to stainless steel, but also lowers corrosion resistance. The more carbon there is, the more chromium be added, because carbon offsets 17 times its own weight in chromium to form carbides, thus reducing chromium available for resisting corrosion.

CHROMIUM - A blue white metal, chromium is the most important element providing corrosion resistance in stainless steel. By adding 12% chromium to ordinary steel, Stainless Steel is formed. Chromium offsets the corrosive effects of carbon found in steel and is the primary factor in the ability of stainless steel to form a passive film on its surface providing corrosion resistance.


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