Welding
Joining metallic parts by coalescence using heat, pressure or both. Weld quality affects structural integrity, fatigue life and leak tightness, so welding must be tightly controlled and periodically requalified.
Special Processes Information
Each of these special processes can have characteristics that cannot be fully verified on every part without damage or excessive cost. They therefore require initial qualification and periodic re-validation to demonstrate that the process, equipment and personnel consistently produce conforming product.
Chemical Processing
Surface finishing and conversion processes relying on controlled chemical reactions. Coating performance depends on bath chemistry, cleanliness and time, requiring strong process control and periodic performance testing.
Electronics
Manufacture and assembly of electronic hardware where solder quality, cleanliness and control directly affect reliability, especially for high-reliability aerospace and defence systems.
Composites
Fibre-reinforced polymer and bonded structures where cure conditions, fibre orientation and adhesive control govern strength, stiffness and damage tolerance.
Elastomer Seals
Moulded and fabricated elastomeric seals where compound selection, cure and dimensional control determine sealing performance over time, pressure and temperature.
Heat Treatment
Thermal processes used to modify microstructure and mechanical properties of metals. Furnace control and pyrometry directly determine hardness, strength and toughness.
Materials Testing & Inspection
Laboratory tests and measurements used to characterise materials and components. Test methods themselves are special processes that must be qualified and routinely checked.
Nonconventional Machining
Material removal processes using electrical, chemical or laser energy. Subsurface damage and recast layers may be hidden, so parameters must be carefully validated.
Non-destructive Testing
Inspection methods that detect flaws without damaging the part. System performance and operator competence must be qualified and periodically demonstrated.
Additive Manufacturing: Directed Energy Deposition
Directed Energy Deposition processes that melt feedstock as it is deposited. Build quality depends on path planning, melt pool stability and feed control.
Additive Manufacturing: Powder Bed Fusion
Powder Bed Fusion processes where a laser or electron beam fuses powder in layers. Parameters and powder quality govern density, defects and mechanical performance.
Additive Manufacturing: Sheet Lamination
Sheet Lamination processes that bond and cut stacked sheets of material to form parts with tailored properties and geometry.
Additive Manufacturing: Material Extrusion
Material Extrusion processes that extrude thermoplastic or filled feedstock through a nozzle to build parts layer by layer.
Additive Manufacturing: Material & Binder Jetting
Material Jetting and Binder Jetting processes that deposit droplets of build material or binder to form highly detailed parts.
Additive Manufacturing: Vat Photopolymerization
Vat Photopolymerization processes that cure liquid photopolymer in a vat using light, giving fine detail and smooth surfaces when validated correctly.