Metal Forming and Machining Techniques
Metal Forming Techniques
When you want to obtain metal parts of complex geometry, melting and forming processes are used. This involves pouring the molten material into a mold containing the hollow shape of the object you want to create, and then letting it cool.
Deformation Techniques
These techniques consist of subjecting the material to continuous deformation until it reaches the desired size and shape. Examples include:
- Forging: A process by which a material, heated to an optimum temperature, undergoes a process of continuous deformation.
- Rolling: This technique can be done cold or hot. It involves passing a material between two rollers to achieve the desired shape or profile.
- Extrusion: The material is forced to pass, under pressure, through a die that has a specific shape.
- Drawing: This involves pulling strongly from the end of a rod, forcing it to pass through a series of holes of decreasing diameter.
Separation Techniques
As the name suggests, the separation of the material occurs without the evolution of chips, and could be by cutting or mechanical shearing. Among these techniques, the following stand out:
- Hand and power saws or alternative tape.
- Special procedures such as removal of material by abrasion using die-cutting machines.
- Bow saws: Milling tools used manually.
- Step: The distance between two consecutive teeth.
- Setting: This consists of alternately bending the teeth of the saws in both directions.
- Band Saws: These consist of a saw blade.
- Die-cutting: A special shear cutting technique in which there is no detachment or rejection of material.
- Abrasive Cutting: Cutting by abrasion with an abrasive wheel of appropriate and small thickness causes wear located in a part to produce the cut.
- Oxyfuel Cutting: A technique with which you can cut some metals and alloys, using heat and oxygen. The temperature must be raised to reach the optimum combustion temperature.
- Riveting: A mechanical operation that allows joining sheets or similar materials of small thickness by means of rivets.
Welding Techniques
Welding is a technique that consists of joining metal parts by applying heat. You can join by applying heat directly to the areas of the pieces that are in contact. If they have a similar composition, they are called homogeneous welds, and if they are different, heterogeneous welds.
- Soft Soldering: Heterogeneous welding. Used for tin, and tin-copper-zinc alloys.
- Arc Welding: Homogeneous welding. Joining processes fixed by heat, but used in steel. It is formed between two conductors called electrodes. It is based precisely on maintaining a stable spark, which requires a generator or transformer.
Machining Techniques
- Filing: The operation of shaping a piece by removing material in the form of filings.
- Sanding: A technique to polish metal and wood surfaces to obtain a smooth finish.
- Scraping: A mechanical finishing operation that involves removing small metal chips.
- Tapping/Threading: A mechanical operation that involves the carving of threads.
- Drilling: A mechanical operation for making round holes using a drill. Drills are machines with rotating movements and a feed rate for the drill bits.
- Planing: Operating systems for surface machining machines (Shaper).
- Abrasive Blasting: Sanders are responsible for moving a replaceable fabric coated with an abrasive material.
- Grinding: A mechanical finishing operation that involves wearing down the surfaces of parts to achieve high precision.
- Milling: An operation (using a milling machine) where the rotation allows the machining of the surfaces of the parts as they are moved.
- Turning: A mechanical operation that consists of rotating parts on their axis.