New methods of manufacture

Question 1

What is electrohydraulic forming?

Answer 1

An electrical pulse generates a shock wave in the fluid (water) that forces the material (usually metal) into the shape of the former. The air is evacuated from the mould prior to forming so this does not prevent the material forming effectively.

Question 2

What are the advantages of electrohydraulic forming?

Answer 2

high precision for complex shapes
rapid processing - fast, single staged
minimal material wastage
can enhance material propeties due to high strain involved in the process
energy efficient

Question 3

What are the disadvantages of electrohydraulic forming?

Answer 3

high initial investment
complex
limited material compatibility
limited scalability
potential surface imperfections
safety risks due to high energy levels
environmental impacts (water, noise pollution)

Question 4

What is direct metal laser sintering (DMLS)?

Answer 4

DMLS is an additive manufacturing technique used to produce metal parts. Metals in the form of a powder are sintered using a powerful laser layer by layer formed from 3D CAD models.

Question 5

What are the advantages of DMLS?

Answer 5

highly intricate and complex shapes
design freedom
material efficiency
rapid prototyping
customisation - one-off/ low-volume production
material diversity
high precision
functional prototypes

Question 6

What are the disadvantages of DMLS?

Answer 6

surface roughness
may need support structures to prevent distortion and maintain accuracy
limited material selection
expensive - particularly for high-volume production
size limitations

Question 7

What is electrohydraulic forming used for?

Answer 7

automotive body and frame parts
aeroplane parts
shipbuilding
appliances
electronic body parts
defense industry

Question 8

What is DMLS used for?

Answer 8

aerospace parts such as turbine blades
rapid prototyping for cars
patient-specific implants
dental crowns and bridges
creating moulds, dies and tooling inserts
defense industry

Question 9

What are the advantages of fibre injection moulding?

Answer 9

increased strength and stiffness
enhanced impact resistance
improved dimensional stability
weight reduction
design flexibility
cost-effective
corrosion resistance (glass/aramid)
low wastage

Question 10

What is fibre injection moulding?

Answer 10

Short fibres (usually glass, carbon or aramid fibres) are mixed into the plastic resin before they are injected into a mould cavity under high pressure and temperature. The fibres are uniformly distributed throughout the plastic matrix, providing reinforcement to the final moulded part.

Question 11

What are the disadvantages of fibre injection moulding?

Answer 11

higher material costs
complex processing
textured/rough surface appearance
equipment and tooling costs
limited material selection
environmental concerns
quality control consistency
potential brittleness

Question 12

What is fibre injection moulding used for?

Answer 12

car panels
aeroplane panels
electronic casing and housing
bicycle frames
prosthetics
machine housing

Question 13

What is wood particle injection moulding?

Answer 13

Wood flour or fibres are added to a polymer resin and the mixture is injected into a mould cavity under high pressure and temperature.

Question 14

What are the advantages of wood particle injection moulding?

Answer 14

increased strength and stiffness
dimensional stability
reduced weight
cost-effective
environmentally friendly
improved thermal insulation
reduced tool wear
sound damping
aesthetics - natural wood look

Question 15

What are the disadvantages of wood particle injection moulding?

Answer 15

moisture sensitivity
end of life concerns
complexity of processing

Question 16

What is wood particle injection moulding used for?

Answer 16

furniture
construction - decking, railing, trims, fencing
car parts - door panels, dashboard accessories
packaging materials - pallets, crates, containers
architechtural elements - decorative trims

Question 17

What is laser beam welding?

Answer 17

Welding technique using a highly focused laser beam to join metal components together. It is a precise and efficient welding method commonly used to join thin to thick metal parts with minimal heat input.

Question 18

What are the advantages of laser beam welding?

Answer 18

no filler rod required
accurate
deep welds possible
low running and maintenance costs
automation
high quality
environmentally friendly

Question 19

What are the disadvantages of laser beam welding?

Answer 19

high equipment cost
sensitive to surface contaminations suc has oxides, oils and coatings
safety hazard
material limitations - highly reflective or low thermal conductivity materials need specialised equipment or techniques
skilled expertise required
environmental sensitivity - temperature, humidity and air quality can affect the performance of the laser beam

Question 20

What is laser beam welding used for?

Answer 20

joining car body parts
joining aircraft fuselage parts
assembling delicate electronic components such as sensors and semiconductors
surgical instruments, implants and devices
jewelry
repair and refurbish moulds, dies and punches
sheet metal fabrication and pipe welding

Question 21

Why do companies invest in new manufacturing methods?

Answer 21

long term efficiency
reduce labour costs
aesthetic qualities
waste reduction
market advantage
reduce energy costs

Question 22

What is computational fluid dynamics (CFD)?

Answer 22

CFD is a tool to simulate fluid or gas flow virtually to help designers improve aerodynamics. It uses sophisticated computer modelling to predict the flow of gases or fluids in or around a product. Commonly used for cars, but can be used for boats/ships and other products where drag reduction is desired. It is cheaper than wind tunnel testing.

Question 23

What is finite element analysis (FEA)?

Answer 23

FEA is a modelling tool that allows engineers and designers to test and analyse individual components or whole systems against loads and other simulated stresses, such as wind or vibrations. Critical design flaws can be identified early before production is started.

Question 24

What are the 3 main types of rapid prototyping?

Answer 24

Stereolithography (SLA)
Fused filament fabrication (FFF) or fused deposition modelling (FDM)
Selective laser sintering (SLS)

Question 25

What is stereolithography (SLA)?

Answer 25

SLA is a type of 3D printing that uses a liquid resin cure by UV light to create solid objects layer by layer from the bottom up.

Question 26

What are the advantages of SLA?

Answer 26

high precision
fast printing speed
smooth surface finish
complex geometries
high quality
minimal warping
low maintenance

Question 27

What are the disadvantages of SLA?

Answer 27

cost of materials
limited sizes
SLA resins are sensitive to UV rays so need to be stored properly
brittleness
safety concerns - photopolymer resins may emit volatile organic compounds (VOCs)