Bidford-on-Avon, Warwickshire. Mon to Fri.01789 224228

Manufacturing services · Chapter E · Method 27

Die casting

Molten aluminium or zinc is injected at high pressure into a steel die, producing accurate, thin-walled metal parts in high volumes.

9,000-tonne high-pressure die-casting cell.
9,000-tonne high-pressure die-casting cell. Representative process photo · Wikigbf · CC BY-SA 4.0 · Wikimedia Commons

How it works

Die casting, step by step.

A labelled schematic of the process (not to scale), and the four steps every job goes through.

Labelled diagram showing how die casting works
Schematic · not to scale. Drawn by TCI Group.
STEP 01

Die

Machine a hardened steel die with cores and slides.

STEP 02

Shot

Molten metal is ladled into the shot sleeve.

STEP 03

Inject

A plunger drives metal into the die at speed.

STEP 04

Trim

Eject, trim gates and flash, machine critical features.

Reference figures

What to expect.

Typical industry values to help you plan. We agree the figures for your part on the drawing.

Tolerance±0.25 mm + 0.025 mm/mmDie plus shrink
Repeatability±0.10 mmPart to part
FinishRa 1.6 µmAs cast, typical
Volume1,000s – millionsPer die
MaterialsAluminium alloys (A380, ADC12), zinc (Zamak), magnesium.
FinishesAs cast; powder coated, painted, anodised (limited), plated or machined.
Design guidance
  • Add draft to all walls; keep walls uniform.
  • Use ribs and coring to save metal.
  • Supply both as-cast and machined models.
Best suited toHousings, heat sinks, brackets and hardware.
Watch-outsHigh die cost; parting lines, gate marks and ejector marks are visible.

More in chapter E

Other methods in Metal production

Next step

Not sure this is the right route?

Send a sketch, photo, sample or CAD file with your quantity and target date. We will recommend the most sensible route and explain the trade-offs before quoting.

Reference figures are typical published industry values for planning, not a guarantee; final tolerances, materials and finishes are agreed in writing for each project.