The strength and resistance levels of metals is generally calculated and recorded at an ambient temperature, or room temperature. Once a metal object has been manufactured into a usable object, the strength and level of decay that affects the object can be affected by the temperature of storage areas and the relative humidity of the environment.
The classification of metals is divided into ferrous and non-ferrous metals; each type of metal has specific temperature requirements that affect the performance of the metal. A ferrous metal is one that contains iron and small amounts of other metals, these other metals can be added to increase the specific requirements of the metal or alloy. Ferrous metals are magnetic and have little corrosion resistance. Ferrous metals reach their maximum strength and resistance levels at about 392 degrees Fahrenheit, according to Roychem. Metals that can be worked in manufacturing process at high temperatures include tungsten, tantalum, chromium, steel and steel alloys.
Non-ferrous metals do not contain iron, making them more resistant to corrosion and not magnetic. The majority of types of non-ferrous metals operate at their optimum strength and resistance qualities at around room temperatures. Types of non-ferrous metals include aluminum, lead, copper and zinc. Some non-ferrous metals and alloys can operate effectively at less than freezing temperatures. Aluminum alloys are generally used for parts operating at -454 degrees Fahrenheit.
All metals react differently under stress at high temperature and in a manufactured form. When a metal reaches a high temperature, it may deteriorate (creeep) and components with a metal object may deform or be damaged. Sub-zero temperatures show little change in the tensile strength of metals. At temperatures close to the boiling point of a metal, the elasticity of the metal is reduced and the metal loses its solid form.
Older metal objects can be affected at high and low temperatures, with lower temperatures often providing a better environment for preserving metal objects. At higher temperatures atoms and molecules within a metal move more quickly, increasing the rate of decay within the chemical reaction of the metal. Chemical and mechanical deterioration both affect inorganic materials, such as metals. Mechanical deterioration can cause changes in the color and shape of an object, with the damage caused by mechanical deterioration resulting from high storage temperatures leading to splitting and cracking of the metal object. High temperatures can be linked to high moisture levels in an environment, also known as relative humidity, that can increase the decay of a metal object.
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