Cambridge Syllabus Notes

Materials Processing in Industry – Fabrication (Cambridge A‑Level Design & Technology 9705)

Fabrication is the collection of processes that convert raw material into a finished component or assembly by removing, adding, reshaping or joining material. It underpins almost every product studied in the syllabus and links directly to design, quality, health & safety and sustainability considerations.

Key Objectives of Fabrication

Achieve the required geometry, dimensions and tolerances.
Obtain the mechanical properties (strength, stiffness, toughness, ductility) specified in the design brief.
Provide an appropriate surface quality and finish for function and aesthetics.
Minimise material waste, production cost and lead‑time.
Ensure compliance with health, safety, environmental and quality‑system requirements.

Full List of Processes Required by the 9705 Syllabus

The syllabus expects knowledge of the following 16 categories. The sections below cover each category, give key examples, and highlight typical materials, advantages, limitations and applications.

Shaping (cutting, die‑cutting, laser, water‑jet, plasma, CNC milling, sawing)
Forming (rolling, extrusion, forging, bending, deep drawing, stamping/punching, tube‑bending)
Redistribution (re‑grinding, re‑machining, re‑cutting, re‑forming)
Wastage Management (scrap recycling, off‑cut utilisation)
Fabrication (assembly of parts by joining, fastening, bonding)
Joining (welding, resistance spot, friction stir, adhesive bonding, mechanical fastening, brazing/soldering, ultrasonic welding)
Material‑Enhancement (heat‑treatment, surface‑coating, carburising, nitriding, anodising, plating, shot‑peening)
Printing (offset, flexography, gravure, digital ink‑jet/UV, sublimation, pad printing)
Colour‑Separation (CMYK workflow)
Finishes (painting, powder coating, polishing, sand‑blasting, electropolishing)
Testing & Inspection (dimensional, non‑destructive, destructive, surface‑roughness, hardness)
Digital Manufacturing (CAD, CAM, CNC, robotics, AI, VR/AR, IoT, digital twin)
Additive Manufacturing (FDM, SLA, SLS, DMLS/SLM)
Quality Systems (ISO 9001, Six‑Sigma, statistical process control)
Health, Safety & Sustainability (risk assessments, waste reduction, energy efficiency)

1. Cutting & Shaping Processes

Cutting removes material to obtain the desired shape. Selection depends on material type, thickness, required tolerance, production volume and availability of digital control.

Process	Typical Materials	Key Advantages	Key Limitations	Typical Applications
Mechanical Sawing (band, circular, hacksaw)	Metals, plastics, timber	Low capital cost; good for thick sections	Limited precision; slower for thin sheets	Structural steel sections, timber framing, pipe trimming
CNC Milling (router, vertical/horizontal)	Aluminium, brass, plastics, composites	High dimensional accuracy; repeatable; programmable	Tool wear; higher setup cost than manual sawing	Tool‑and‑die making, aerospace brackets, mould bases
Laser Cutting	Sheet metal, plastics, composites	Very high precision; narrow kerf; fast for thin sheets	High capital cost; limited thickness (≈25 mm for steel)	Automotive panels, decorative metalwork, prototype parts
Water‑Jet Cutting	Metals, stone, glass, composites, ceramics	No heat‑affected zone; can cut very thick material	Water consumption; slower than laser for thin sheets	Aerospace components, architectural panels, art installations
Plasma Cutting	Conductive metals (steel, aluminium, copper)	Fast for thick steel; relatively low equipment cost	Rougher edge finish; limited to conductive materials	Shipbuilding, heavy‑duty steel fabrication, structural frames
Die‑Cutting (mechanical or CNC)	Paper, cardboard, thin plastics, foil, fabric	Very rapid for high‑volume flat parts; consistent shape	Initial die cost; limited to 2‑D shapes	Packaging blanks, labels, gaskets, decorative inserts
Laser & CNC Vinyl Cutting (digital printing sub‑process)	Vinyl, thin polymer films, cardboard	Rapid production of graphics, signage, packaging	Limited to low‑thickness substrates	Label making, vehicle graphics, custom decals

2. Forming & Shaping Processes (No Material Loss)

Forming changes the shape of a workpiece by plastic deformation, either hot (above recrystallisation temperature) or cold (room temperature). The force required can be approximated by F ≈ σ_f A_p, where σ_f is the flow stress and A_p the projected area.

Process	Typical Materials	Typical Products	Key Considerations
Rolling (flat‑roll, shape‑roll)	Steel, aluminium, copper alloys	Sheets, plates, structural sections (I‑beams, channels)	Roll gap, reduction per pass, lubrication, temperature
Extrusion (direct, indirect)	Aluminium, magnesium, plastics, composites	Window frames, railway rails, tubing, profiles	Die design, extrusion ratio, temperature control, back‑pressure
Forging (open‑die, closed‑die, roll‑forging)	Steel, aluminium, titanium, nickel alloys	Gear blanks, connecting rods, aerospace brackets	Strain‑rate, grain flow, die material, pre‑heating
Bending (press brake, roll‑bending)	Sheet metal, thin plate	Bracket edges, chassis members, ducts	Material thickness, bend radius, spring‑back, tooling
Deep Drawing	Aluminium, steel, copper alloys	Cans, automotive body panels, kitchen sinks, fuel tanks	Blank holder force, draw ratio, lubrication, die radius
Stamping / Punching	Sheet metal, plastics	Gaskets, perforated sheets, complex outlines, embossing	Tool wear, clearance, material ductility, punch‑die alignment
Tube‑Bending (rotary, mandrel)	Steel, aluminium, stainless tubing	Automotive exhausts, hydraulic lines, structural frames	Wall thickness, bend radius, spring‑back, tooling wear

3. Redistribution & Re‑Processing

Re‑grinding / Re‑machining – removes excess material from a previously machined part to meet tighter tolerances.
Re‑cutting – uses a secondary cutting operation (e.g., laser trimming of a CNC‑cut blank) to achieve finer features.
Re‑forming – heat‑treats or cold‑works a part to correct distortion or improve properties after an earlier operation.

4. Wastage Management

Effective waste control reduces cost and environmental impact.

Scrap Recycling – collection, segregation and remelting of metal off‑cuts.
Off‑cut Utilisation – nesting software for sheet‑metal, nesting of polymer sheets, or using scrap for secondary products (e.g., decorative panels).
Process Optimisation – selecting the most material‑efficient cutting method (laser vs. die‑cut) and nesting strategy.

5. Joining Processes

Joining creates permanent or semi‑permanent assemblies. Choice depends on material compatibility, required strength, service environment and cost.

Process	Typical Materials	Relative Strength	Key Design / Process Considerations	Typical Uses
Arc Welding (MIG, TIG, SMAW)	Carbon steel, stainless steel, aluminium, copper alloys	High	Heat input, filler metal, joint geometry, shielding gas, distortion	Structural frames, automotive bodies, pressure vessels
Resistance Spot Welding	Thin steel sheets, aluminium alloys (with appropriate electrodes)	Medium‑High	Current density, electrode force, sheet thickness, nugget size, heat‑affected zone	Automotive body panels, appliance housings, sheet‑metal assemblies
Friction Stir Welding (FSW)	Aluminium alloys, copper, magnesium, some steels	High (defect‑free joint)	Tool design, rotational speed, travel speed, shoulder pressure	Aerospace wing skins, marine hulls, high‑strength aluminium structures
Adhesive Bonding	Metals, plastics, composites, glass	Medium (depends on adhesive)	Surface preparation, cure temperature/time, adhesive type, joint design (overlap, fillet)	Aerospace panels, consumer electronics, automotive interior trim
Mechanical Fastening (Bolts, Rivets, Screws, Threaded Inserts)	All engineering materials	Variable (depends on fastener size & grade)	Torque, preload, fatigue life, accessibility for inspection, corrosion protection	Aircraft structures, heavy machinery, modular furniture, automotive chassis
Brazing / Soldering	Copper, brass, aluminium (with special filler), ceramics (with active filler)	Medium‑High	Filler alloy melting point, capillary action, joint clearance, flux selection	Heat exchangers, HVAC components, electronic enclosures, jewellery
Ultrasonic Welding	Thermoplastics, some metals (e.g., aluminium with interlayer)	Medium	Amplitude, pressure, welding time, part geometry	Medical device housings, automotive interior components, plastic‑to‑metal assemblies

6. Material‑Enhancement Processes

These processes modify the bulk or surface properties of a material without changing its overall shape.

Process	Purpose	Typical Materials	Key Considerations
Heat‑Treatment (annealing, normalising, quenching, tempering)	Adjust hardness, strength, ductility, relieve stresses	Carbon steel, alloy steel, aluminium, titanium	Temperature, soak time, cooling rate, distortion risk
Carburising & Nitriding	Surface hardening of steels	Low‑alloy steels, tool steels	Case depth, carbon/nitrogen potential, post‑quench tempering
Anodising (electro‑chemical oxidation)	Increase corrosion resistance, allow dyeing, improve wear resistance	Aluminium, magnesium alloys	Bath composition, voltage, time, sealing step
Electro‑Plating (zinc, nickel, chrome)	Improve corrosion resistance, appearance, wear resistance	Steel, brass, aluminium (with appropriate strike layer)	Adhesion, thickness control, environmental regulations
Shot Peening	Introduce compressive surface stresses to improve fatigue life	Steel, aluminium, titanium alloys	Shot size, coverage, intensity, surface finish
Surface Coating (powder coating, painting, varnish)	Protect against corrosion, provide colour/texture, add wear resistance	Metals, polymers, composites	Pre‑treatment, curing temperature, thickness, environmental impact

7. Printing & Colour‑Separation Processes

Printing transfers a 2‑D image onto a substrate. The syllabus requires knowledge of conventional printing technologies and the CMYK colour‑separation workflow.

Printing Technology	Substrate(s)	Key Features	Typical Uses
Offset Lithography	Paper, cardboard, thin plastics	High speed, excellent colour fidelity, economical for large runs	Books, magazines, packaging graphics, brochures
Flexography	Plastic film, corrugated board, metallic foil, non‑porous substrates	Fast, can print on uneven surfaces, uses quick‑dry inks	Food packaging, labels, flexible packaging, cartons
Gravure (Rotogravure)	Paper, thin plastic, aluminium foil	Very high image quality, long‑run cost‑effective, continuous process	High‑volume magazines, cigarette packs, gift wrap, wallpaper
Digital Ink‑jet / UV Printing	Paper, canvas, wood, metal, glass, polymers	No plates; on‑demand, variable data, quick set‑up	Custom signage, short‑run packaging, prototypes, large‑format graphics
Sublimation Printing	Polyester fabrics, coated metals, ceramics	Ink turns to gas and embeds into substrate; vibrant, permanent colours	Sportswear, promotional items, interior décor, signage on coated metal
Pad Printing (Tampon)	Irregular 3‑D surfaces (plastic, glass, metal, ceramics)	Transfers fine details onto complex shapes; multi‑colour possible	Medical device markings, automotive badges, consumer‑goods branding
Die‑Cut Printing (combined die‑cut & print)	Paper, cardboard, thin plastics, foil	Simultaneous cutting and printing; high repeatability	Packaging blanks, greeting‑card inserts, promotional die‑cut shapes

CMYK Colour‑Separation Workflow

Capture the full‑colour source image (RGB, scanned artwork, or digital file).
Convert the image into four separations: Cyan, Magenta, Yellow and Black (Key).
Each separation is transferred to a printing plate (or digital equivalent) that carries only that colour’s image.
During printing, the four inks are over‑printed in precise registration; the super‑position reproduces the original colour gamut.
Spot colours or special inks may be added as a fifth plate where required.

8. Additive Manufacturing (AM)

AM builds parts layer‑by‑layer directly from a digital model. It is ideal for low‑volume, complex geometry and rapid prototyping.

AM Technology	Material(s)	Typical Layer Thickness	Key Design Considerations	Common Applications
Fused Deposition Modelling (FDM)	Theroplastic filaments (PLA, ABS, PETG, Nylon, TPU)	0.1–0.4 mm	Support structures for overhangs, build orientation affects strength, nozzle temperature	Prototypes, jigs, low‑cost functional parts, educational models
Stereolithography (SLA)	UV‑curable photopolymer resin	0.025–0.1 mm	Support removal, post‑cure, excellent surface finish, limited build size	Dental models, jewellery prototypes, high‑detail visual models, micro‑features
Selective Laser Sintering (SLS)	Powdered polymers (Nylon, TPU) or metal powders (AlSi10Mg, stainless steel)	0.1–0.2 mm	No support needed (unsintered powder acts as support), part orientation influences mechanical anisotropy, powder handling safety	Functional aerospace brackets, custom tooling, small‑batch production, lattice structures
Direct Metal Laser Sintering (DMLS) / Selective Laser Melting (SLM)	Stainless steel, titanium, Inconel, aluminium alloys, cobalt‑chrome	0.02–0.05 mm	Powder handling, build chamber atmosphere (inert gas), post‑processing (heat‑treatment, machining), residual stresses	Medical implants, high‑performance aerospace components, tooling inserts
Electron Beam Melting (EBM)	Titanium alloys, cobalt‑chrome, aluminium alloys	0.05–0.1 mm	Vacuum environment, high build temperature reduces residual stress, surface roughness higher than SLM	Aerospace structural parts, orthopaedic implants, high‑temperature components

9. Digital Technology in Fabrication

Digital tools integrate design, manufacturing and information flow, supporting the modern “smart factory”.

CAD (Computer‑Aided Design) – 3‑D modelling, assembly simulation, tolerance analysis, design for manufacture (DFM).
CAM (Computer‑Aided Manufacturing) – Tool‑path generation for CNC milling, laser cutting, water‑jet, plasma, and robotic machining; optimisation of feed, speed and tool wear.
Robotics & Automation – Pick‑and‑place, welding robots, CNC pallet changers, collaborative robots (cobots) for flexible cell operation.
Artificial Intelligence & Machine Learning – Predictive maintenance, process optimisation, defect detection via computer vision, adaptive control of laser power.
Virtual Reality (VR) & Augmented Reality (AR) – Virtual prototyping, assembly training, real‑time overlay of machining data on the workpiece.
Internet of Things (IoT) & RFID – Real‑time monitoring of machine parameters, inventory tracking of raw material and finished parts, condition‑based alerts.
Digital Twin – A virtual replica of a manufacturing cell used for process optimisation, what‑if analysis and rapid re‑configuration.
Cloud‑Based Manufacturing Execution Systems (MES) – Centralised scheduling, data collection, traceability and quality reporting.

10. Finishing Processes

Finishing improves appearance, corrosion resistance, wear resistance and sometimes functional performance.

Process	Typical Materials	Purpose	Key Considerations
Painting (spray, dip, electro‑static)	Metals, polymers, composites	Corrosion protection, colour, surface texture	Surface preparation (cleaning, priming), cure temperature, VOC regulations
Powder Coating	Metals (steel, aluminium, zinc‑die‑cast)	Durable, uniform finish, high corrosion resistance	Electro‑static application, oven cure, thickness control
Polishing / Buffing	Metals, plastics, glass	Improve surface smoothness, aesthetic shine, reduce friction	Abrasive grade, process time, risk of surface deformation
Sand‑blasting (Abrasive Blasting)	Metals, glass, stone	Surface cleaning, roughening for paint adhesion, decorative texture	Abrasive type, pressure, environmental dust control
Electropolishing	Stainless steel, aluminium, copper	Remove micro‑peaks, improve corrosion resistance, bright finish	Electrolyte composition, current density, temperature, safety
Anodising (see Material‑Enhancement)	Aluminium, magnesium	Protective oxide layer, colour‑dyeing, wear resistance	Bath chemistry, voltage, sealing step

11. Quality Systems & Testing

Ensuring that fabricated components meet design specifications is a core requirement of the syllabus.

Dimensional Inspection – Calipers, micrometres, CMM (Coordinate Measuring Machine), optical comparators, laser scanners.
Surface‑Roughness Measurement – Stylus profilometers, interferometers, visual comparison charts.
Hardness Testing – Rockwell, Brinell, Vickers, Shore (for polymers).
Non‑Destructive Testing (NDT) – Ultrasonic, radiography, magnetic particle, dye penetrant, eddy‑current.
Destructive Testing – Tensile, compression, bend, impact (Charpy), fatigue, fracture toughness.
Statistical Process Control (SPC) – Control charts, process capability (Cp, Cpk), Six‑Sigma methodology.
Quality Management Systems – ISO 9001, audit trails, corrective‑preventive actions (CAPA), traceability of raw material batches.

12. Health, Safety & Sustainability

Risk assessments for cutting, welding and AM (laser safety, fume extraction, powder handling).
Personal protective equipment (PPE): eye protection, hearing protection, gloves, respirators.
Energy‑efficient processes (e.g., water‑jet vs. laser for thick material, optimisation of CNC tool‑paths).
Material recycling schemes for metal scrap, polymer waste, and spent AM powders.
Design for Disassembly (DfD) to facilitate end‑of‑life recycling.

Summary Table – Alignment with Syllabus Requirements

Syllabus Requirement	Coverage in Notes
Shaping / Cutting (incl. die‑cutting)	Section 1 – detailed table of 7 cutting methods
Forming (rolling, extrusion, forging, bending, deep drawing, stamping, tube‑bending)	Section 2 – comprehensive table
Redistribution & Re‑processing	Section 3 – list of re‑grinding, re‑cutting, re‑forming
Wastage Management	Section 4 – scrap recycling and nesting
Fabrication & Joining	Section 5 – extensive joining table
Material‑Enhancement (heat‑treatment, surface‑coating, hardening)	Section 6 – material‑enhancement table
Printing & Colour‑Separation	Section 7 – printing technologies and CMYK workflow
Finishes	Section 10 – finishing processes table
Testing & Quality Systems	Section 11 – inspection, NDT, SPC, ISO 9001
Digital Manufacturing	Section 9 – CAD/CAM, robotics, AI, IoT, digital twin
Additive Manufacturing	Section 8 – AM technologies table
Health, Safety & Sustainability	Section 12 – safety, energy, recycling, DfD

These notes now provide a complete, syllabus‑aligned overview of fabrication processes, with clear structure, tables, examples and the technical depth required for Cambridge A‑Level Design & Technology (9705).

Fabrication.