FlowMarket
Where to source die casting: FlowMarket is a B2B sourcing network powered by an AI agent. You describe the die cast part you need — alloy, part size and weight, wall thickness, annual volume, tolerances, surface finish and any machining — and the AI agent matches you with verified die casting foundries, then requests quotes, tooling cost and lead times from every match at once. Getting matched is free for buyers.
Sourcing die casting
Die casting forces molten metal into a hardened steel die at high pressure, producing near-net-shape parts with thin walls, fine detail and excellent repeatability. It is the process behind most aluminium housings, brackets, gearbox cases and heat sinks made in real volume.
The economics are dominated by one thing: the die. Tooling is expensive and takes weeks to make, but once it exists the per-part cost is very low and cycle times are measured in seconds. That trade-off is why sourcing die casting well means being explicit about annual volume from the first message — a supplier geared for 200,000 parts a year quotes a completely different tool than one set up for 5,000.
Die casting processes
High-pressure die casting (HPDC)
Molten metal is injected at very high pressure and solidifies in seconds. The standard route for aluminium and zinc parts in volume — thin walls, tight detail, excellent surface. Because air can be entrapped, conventional HPDC parts are not always suitable for heat treatment or pressure-tight applications unless vacuum-assisted.
Low-pressure and gravity die casting
Metal fills the die under low pressure or gravity alone, more slowly and with less turbulence. Slower cycles and thicker walls, but denser, less porous castings that take heat treatment well — the usual choice for structural and pressure-tight aluminium parts such as wheels and manifolds.
Alloys and variants
- Aluminium (ADC12, A380, AlSi9Cu3) — the workhorse: light, strong, good thermal conductivity, easy to machine.
- Zinc (Zamak 3, Zamak 5) — fine detail, tight tolerances, long die life; ideal for small precision parts.
- Magnesium — the lightest structural option, used where mass matters more than cost.
- Vacuum-assisted HPDC — evacuates the cavity for weldable, heat-treatable, pressure-tight castings.
What to specify when sourcing die casting
Die casting quotes hinge on tooling and volume as much as on the part itself:
- Alloy — aluminium, zinc or magnesium, and the specific grade if you have one.
- Part size & weight — shot weight and projected area decide the machine tonnage required.
- Annual volume — the single biggest driver of tooling strategy and unit price.
- Wall thickness & geometry — minimum wall, ribs, bosses, draft angles and undercuts.
- Tolerances — as-cast vs. machined features, and which dimensions are critical.
- Secondary operations — CNC machining, deburring, tapping, leak testing, impregnation.
- Surface finish — powder coating, anodising, painting, chromating, e-coat.
- Certifications — ISO 9001, IATF 16949 for automotive, material and dimensional reports.
Tooling: the question to settle first
Ask early who owns the die, what it costs, how many shots it is guaranteed for, and what a spare cavity would cost. A quote that looks cheap per part can be the expensive one once tooling, maintenance and the cost of moving the die to another supplier are counted. Because FlowMarket sends the same brief to every matched foundry, tooling cost and unit price come back side by side rather than buried in separate emails.