Metalworking Methods: Types and Features Explained

Metals are deeply integrated into our lives in various forms and uses.
However, the original metal materials are completely different from the products we use.
The process of transforming metals into the desired shapes and functions is called metalworking.

In this article, we will explain the most widely used metalworking methods in the industry: machining, casting, welding, forging, extrusion, and sheet metal forming in a simple and detailed way.
We will also cover the principles, pros and cons, and real-life applications of each method.

1. Machining

A technique for shaping metal by cutting away unwanted parts
Machining is the process of removing unnecessary parts of metal material to shape it into the desired form. Common machining methods include turning, milling, drilling, and grinding.

• Key Features: High precision, smooth surface, complex shapes possible
• Applications: Automotive, aerospace, precision machinery parts, molds, tools, medical devices
• Pros and Cons: High precision and versatility, but material waste and high cost

2. Casting

A method of pouring molten metal into a mold to form a shape
Casting involves melting metal at high temperatures and pouring it into a mold, then cooling it to form the desired shape.

• Key Features: Can create large and complex shapes, wide range of alloys
• Applications: Engine blocks, pump housings, piping parts, artistic sculptures
• Pros and Cons: Efficient for mass production, but defects such as air pockets or shrinkage may occur

3. Welding

A technique for permanently joining metals
Welding is the process of joining two or more metals by using heat, pressure, or both to fuse them together.

• Key Features: Strong, permanent joints, essential for large structures, pipelines, and vehicles
• Applications: Bridges, buildings, automotive bodies, pipelines
• Pros and Cons: Strong joints but may lead to thermal distortion and weld defects

4. Forging

A technique for shaping metal by hammering or pressing
Forging involves heating the metal and shaping it by hammering or pressing to form the desired shape. The metal's structure becomes denser, improving its strength and toughness.

• Key Features: Improved mechanical properties (strength, toughness)
• Applications: Automotive crankshafts, gears, aerospace parts, tools
• Pros and Cons: Excellent strength and toughness, but difficult to create complex shapes

5. Extrusion

A technique for forming metal into long shapes by pushing it through a mold
Extrusion involves placing metal into a die and forcing it through to form long shapes like rods, pipes, or profiles.

• Key Features: Continuous production of uniform cross-sectional shapes
• Applications: Window frames, pipes, heat sinks, rails, electrical wires
• Pros and Cons: Ideal for mass production with consistent quality, but complex cross-sections can be challenging

6. Sheet Metal Forming

A technique for cutting, bending, and shaping thin sheets of metal
Sheet metal forming involves cutting, bending, punching, and pressing thin metal sheets into various shapes.

• Key Features: Lightweight structures, suitable for rapid mass production
• Applications: Automotive body panels, electronics enclosures, household appliances, elevators
• Pros and Cons: Fast and cost-effective production, but difficult to create thick or complex 3D shapes

7. Advanced Metalworking Technologies

3D Printing, Laser Processing, Waterjet Cutting
Recently, advanced technologies have been pushing the limits of traditional metalworking.

• 3D Printing: Uses laser to melt metal powder and build up complex shapes layer by layer, ideal for custom or small-batch production
• Laser Processing/Waterjet Cutting: Used for precision cutting and fine detailing of parts with complex patterns

8. Choosing the Right Metalworking Method

Choosing the optimal metalworking method depends on several factors:

• Product requirements (strength, precision, durability)
• Production volume (small vs. large-scale production)
• Shape and size of the part
• Budget and delivery deadlines
• Need for post-processing (heat treatment, surface finishing, etc.)

9. Conclusion

Metalworking methods are selected based on the material properties and the product requirements. Each method—machining, casting, welding, forging, extrusion, and sheet metal forming—has its own strengths and limitations.
In actual industrial applications, a combination of these methods is often used to achieve the desired results.

In the next series, we will dive deeper into real-life applications, quality control, and the latest trends in metalworking!