Alloy material has very important role in our daily life even there won't be a day passed without using alloy. Our utensils in the kitchen, vehicles, computers, mobile phones, chairs etc. are using different type of alloys which means numerous alloys have been made and being used by human beings. Most of the engineering and medical equipment, machinery, tools are made by Alloys.
What is Alloy?
An alloy is a material containing a mixture of two or more metals. An alloy metal can be used to provide increased strength or a lighter weight material.
Properties of Alloy
Various alloys have different properties like strength, malleability, visual attractiveness etc. Copper and tin uses to make Bronze, an important alloy harder than copper. This quality has been utilized for imprint the civilization and history of mankind for thousands of years called bronze age. In our daily life, mankind uses alloys in almost all of the fields that uses metals. Most known elements have involvement in making alloys thus we have tens of thousands of alloy products. Alloys are attractive due to its improved quality for make utilizing the pure elemental metals.
How to make Alloy?
Alloys can be made by combining two or more metal elements while in a molten state or by bonding metal powders. Various alloys have different desired properties such as strength, visual attractiveness, or malleability. The number of possible alloy combination is almost endless since any metal can be alloyed in pairs or in multiples. Some alloys have hardness while some have low melting points and some others have better magnetic or electrical characteristics; some have high corrosion resistant.
These occurs due to changes happened in the internal and external characteristics during the process of making alloys. Corrosion-resistant alloys are readily formed and joined using conventional techniques and equipment. Solid solution alloy products are normally used in the annealed condition.
Age-hardenable alloys are best fabricated in the annealed condition and either directly aged or annealed and aged afterward to achieve high strength. Corrosion-resistant alloys are normally formed at room temperature. If severe deformation is required, it may be necessary to either use multiple deformations with annealing performed between operations or the part may be heated to an elevated temperature at which greater deformation is possible.
After hot forming, parts should be annealed to restore corrosion resistance. In most cases, cold-formed components may be placed in service without annealing. However, if the environment is such that it might induce stress corrosion cracking, the cold-formed parts should be annealed. Age-hardened alloys are not normally used in environments that can induce stress corrosion.
Different Types of Metal Alloys
Bearing alloys: It is being used for accommodating enough pressure under sliding contact with another metal body commonly known as rotating shaft of the motor, generator, vehicles and various types of propellers.
Corrosion-resisting Alloys: Noble metal uses to make corrosion-resistant alloys which initially oxidized and act as separation layer preventing chemical action from other materials or corrosive environment. Stainless steel and aluminum alloy are examples of these alloys.
Super-Austenitic Stainless Steels Alloy (SASS Alloy): During the last decades of the 20th century, stainless steel technology took a giant leap forward with the development of higher nickel stainless steels enhanced by the addition of nitrogen for improved strength and corrosion resistance. These alloys normally contain about 6% molybdenum, so they offer excellent resistance to localized corrosion in reducing and mixed acid environments. They contain sufficient chromium for resistance to oxidizing environments as well.
High-Strength Corrosion-Resistant Alloys: offers corrosion-resistant alloys that are essentially precipitation-hardenable (age-hardenable) versions of their solid-solution counterparts. These products offer the corrosion resistance of the standard alloys but more than twice the strength. In addition, precipitation-hardenable alloys can be fabricated prior to heat treatment when they are relatively soft and ductile and then heat treated afterword to develop high strength.
Other alloys are Dental alloy and Die-casting alloy which are widely used in our daily life.
Combining iron and a small amount of carbon gives variety of steel products. To make different quality of steel alloys, we add molybdenum, nickel, silicon, boron and manganese.