MAGNETISM - As related to stainless steel fasteners, 300 series stainless is non magnetic in its raw material condition. Cold working can sometimes induce traces of magnetism in 300 series, depending on the severity of cold working and chemical composition of the stainless. A rise in magnetism is related to increase in tensile strength and work hardening caused by the heat and friction of cold forming and does not reduce corrosion resistance or cause any molecular change in austenitic raw material. A higher portion of nickel can increase stability in stainless, thus decreasing work hardening and any possibilities of magnetism. Many stainless specs allow 2.0 magnetic permeability which translates to low/medium magnetism.
MANGANESE - A non magnetic metal which improves strength and hardness.
MOLYBDENUM - Nicknamed moly, molybdenum is a metal added to 316 stainless steel, sharply increasing its corrosion resistance to chlorides and sulfates, especially various sulfurous acids in the pulp industry. Molybdenum helps reduce hardness and increase tensile strength at higher temperatures.
NICKEL - A metal added to 300 series stainless to provide corrosion resistance, increased strength in both high and low temperatures, and increased toughness in low temperatures. Nickel lowers the effects of work hardening, thus reducing traces of magnetism caused by cold forming and making materiall1ow more freely in manufacturing.
PASSIVATING - Technically, passivating is a process of dipping fasteners into a nitric acid solution to rapidly form a chromium oxide on the surface of the material, creating a passive film that protects stainless from further oxidation. The purpose of passivating is to remove both grease left from manufacturing and traces of steel particles which may have rubbed off manufacturing tools onto the fastener.
PASSIVE Fll.M - The major characteristic of stainless is its ability to form a thin layer of protection called a passive film on its outside surface. This film results from a continual process of low level oxidation, so oxygen from the atmosphere is needed for the passive film to exist. Once formed it prevents further oxidation or corrosion from occurring. Even if chipped or scratched, a new passive film on stainless will form.
PROOF LOAD - A test load that a fastener must unde_go without showing significant deformation. It is usually 90% of yield strength.
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