International Baccalaureate: Design & Technology
Topic 4: Manufacturing Processes and Techniques
Designers need to understand a wide range of manufacturing processes and techniques to match their knowledge of materials. This topic does not try to encompass all known techniques but outlines and exemplifies the main manufacturing processes and techniques.
It is important to understand how the different processes link together in the manufacture of a product. During manufacture material is usually first shaped crudely and then more precisely into finished parts or components and finally assembled. Some products or components are made by a single process although most require a mixture of processes.
4.1 Manufacturing Processes and Techniques
4.1.1
4.1.1–4.1.2
A finished product may be required in any one of an innumerable number of shapes and sizes, and there are many different techniques by which to produce the final article. These techniques can be categorized into three major groups: shaping, joining and wasting.
4.1.2
Define manufacturing technique
4.1.3
4.1.4
Explain the relevance of bending, moulding, casting and weaving to the process of shaping.
Knowledge of how each technique shapes a product is required.
4.1.5
4.1.6
Explain the relevance of using fasteners, using adhesives, fusing and stitching to the process of joining. Knowledge of how each technique is used to join materials together is required.
4.1.7
4.1.8
Explain the relevance of machining, cutting and abrading to the process of wasting. Knowledge is required of how each technique is used to waste a product.
4.2 Selecting Materials and Techniques
The selection of materials takes into account economic processing and service requirements. Successful products should be evaluated in terms of efficiency and economy of manufacture, as well as performance.
4.2.1
4.2.2
An annotated diagram should be used. Describe the technique of injection moulding.
4.2.3
Advantages—no finishing required, volume production, use of different moulds
Disadvantages—set up costs reduce suitability for low volume production, limitations to the size, shape, etc
Discuss the advantages and disadvantages of injection moulding.
4.2.4
For example, thermal expansivity and toughness. Identify the relevant properties that make a material suitable for injection moulding.
4.2.5
4.2.6
The description should include the use of a mould or former, and a method of cramping.
Describe the technique of lamination.
4.2.7
Advantages—no finishing required, able to form complex shapes and surfaces, can suit large surfaces, able to combine different materials Disadvantages—labour intensive; may require production of a mould; limitations to the glue, size, clamping, shape and angles of curvature
Discuss the advantages and disadvantages of lamination.
4.2.8
For example, toughness and tensile strength. Identify the relevant properties that make a material suitable for lamination.
4.2.9
4.2.10
Describe the technique of sintering.
4.2.11
Discuss the advantages and disadvantages of sintering.
Advantages—no surface machining required compared to casting, suitable for high melting-point materials
Disadvantages—high energy requirements, limitations to the sizes and shapes that can be produced and the materials that can be used
4.2.12
For example, thermal conductivity and hardness. Identify the relevant properties that make a material suitable for sintering.
4.2.13
4.2.14
Use of an annotated diagram is essential. Describe the technique of extrusion.
4.2.15
Advantages—no finishing required, volume production, hollow shapes
Disadvantages—limitation to the size, shape and detail of extruded products
Discuss the advantages and disadvantages (or limitations) of extrusion.
4.2.16
For example, toughness and durability. Identify the relevant properties that make a material suitable for extrusion.
4.2.17
4.2.18
Relate the techniques to a wide range of materials. Describe cutting and machining techniques.
4.2.19
Advantages—versatility and flexibility, range of material suitability
Disadvantages—assembly requirements
Limitations—size, joining processes
Discuss the advantages, disadvantages and limitations of cutting and machining techniques.
4.2.20
For example, toughness and tensile strength. Identify the relevant properties that make a material suitable for cutting or machining.