Casting:
Casting is one of the most common methods used to shape metal. It involves pouring molten metal into a mold and allowing it to solidify.
- Sand Casting:
A mold is made using sand, and molten metal is poured into it. This is commonly used for producing metal parts in large quantities. - Die Casting:
Molten metal is forced into a steel mold under high pressure. Die casting is used for high-precision, complex parts and is often used for aluminum alloys.
Forming processes involve shaping metal by applying forces such as compression, tension, or shear.
- Rolling:
The metal is passed through rollers to reduce its thickness or change its shape. Rolling is commonly used to create sheets, plates, and bars. - Forging:
Metal is heated and shaped by applying compressive force using tools like hammers or presses. This process improves the metal’s strength and grain structure. - Extrusion:
Metal is forced through a die to create long shapes with a constant cross-section, such as pipes, rods, and beams.
Welding and Joining of MetalsWhat is Welding?Welding is a process used to join two or more metal parts by melting the workpieces and adding a filler material to form a strong bond once the molten material cools and solidifies.
- Arc Welding:
A form of welding that uses an electric arc to melt and join metals. Common types of arc welding include MIG welding (Metal Inert Gas), TIG welding (Tungsten Inert Gas), and Stick welding. - Gas Welding:
A welding process that uses a flame produced by a mixture of oxygen and acetylene. It is typically used for welding thinner metals. - Resistance Welding:
Involves applying pressure and passing electric current through the workpieces. It’s commonly used for welding sheet metal in the automotive industry.
Welding Defects:
- Porosity:
Small holes formed in the weld due to trapped gas bubbles. - Cracking:
A break in the weld metal due to stress or improper cooling. - Inconsistent penetration:
Occurs when the weld does not fully penetrate the base metal, leading to a weak joint