Automotive aluminum die casting produces lightweight structural and housing components — battery module brackets, sensor housings, pump bodies, transmission covers — in place of steel weldments or parts machined from billet. CharMax Precision casts these in A380 and A360 on 160 to 1,250 ton cold chamber machines, machines them in-house to ±0.02 mm, and supplies Tier 1 and Tier 2 buyers as a Tier 2 or Tier 3 source, with PPAP-format documentation under ISO 9001:2015.
Automotive aluminum die casting produces lightweight structural and housing components — battery module brackets, sensor housings, pump bodies, transmission covers — in place of steel weldments or parts machined from billet. CharMax Precision casts these in A380 and A360 on 160 to 1,250 ton cold chamber machines, machines them in-house to ±0.02 mm, and supplies Tier 1 and Tier 2 buyers as a Tier 2 or Tier 3 source, with PPAP-format documentation under ISO 9001:2015.
Automotive programs are defined less by the casting itself than by what surrounds it: a mass target set at platform level, a piece price locked into a long-term agreement with annual reductions, a capability requirement that has to hold over hundreds of thousands of parts, and a launch calendar where the tooling window is fixed months in advance. A casting supplier that quotes only the part price and ignores those constraints creates problems at PPAP submission.
We are ISO 9001:2015 certified and not IATF 16949 certified. In practice that means we work as a Tier 2 or Tier 3 source inside a Tier 1 customer's quality system, or direct to an OEM under a customer-specific quality agreement, supplying PPAP-format submissions, control plans, PFMEA input, capability studies and IMDS data. If your program requires an IATF-certified site of record, that needs to be settled at sourcing rather than discovered at audit.
| Typical alloys | A380 for structural parts, A360 for fluid-carrying and sealed housings |
|---|---|
| Typical part weight | 80 g to 6 kg, up to 12 kg on the largest machines |
| Machine range | 160 to 1,250 tons cold chamber |
| Typical annual volume | 5,000 to 500,000+ parts per program |
| Typical wall thickness | 2.5 to 4 mm on structural parts, 1.5 mm minimum |
| As-cast tolerance | ±0.1 mm for the first 25 mm |
| Machined tolerance | ±0.02 mm on bores, sealing faces and datum features |
| Common finishes | Shot blast, chromate conversion, powder coat, wet paint |
| Leak testing | Air-decay testing to your specified pressure and leak rate |
| Documentation | PPAP-format submission, control plan, capability study, IMDS data, material certificate |
| Certification | ISO 9001:2015 — not IATF 16949, supplied as Tier 2 or Tier 3 |
| Lead times | 25 to 40 days tooling, 15 to 25 days production |
Automotive enquiries almost never start with a blank sheet. They arrive as an existing part that costs too much, weighs too much, leaks, or has just lost its supplier. The engineering problem is usually clear; the commercial constraints around it are what make it difficult.
A vehicle programme distributes a kerb-weight reduction across subsystems, and the bracket engineer inherits a number they did not choose. Replacing a steel weldment with a die cast aluminum bracket typically removes 40 to 60% of the mass at similar stiffness, which is why the request lands on a casting supplier's desk.
Long-term agreements fix the price and often build in annual reductions. That makes cycle time, cavity count and machining time decisions you cannot revisit later, so they have to be optimised before the die is cut rather than negotiated afterwards.
Automotive buyers do not ask whether one part measured in tolerance. They ask for Cpk on identified critical characteristics across a capability run, which means the process has to be centred and stable rather than merely capable of passing an inspection.
Coolant pumps, oil housings, thermal management manifolds and EV cooling plates have to hold pressure. Porosity that is harmless in a bracket becomes a rejected part here, especially where machining cuts into a wall and opens a subsurface void into a sealed volume.
Tooling takes 25 to 40 days and samples another 5 to 7. When a design freeze slips, the tooling window absorbs it, and a die change after T1 samples costs weeks unless the tool room is in the same building.
Parts have to remain available for a decade of service demand after the line stops, in batches far smaller than production. Tooling has to be stored, maintained and requalified rather than scrapped at end of production.
High pressure die casting is the process automotive settled on for aluminum volume parts because it attacks mass, cost and part count at the same time. A single casting replaces a stamped-and-welded assembly, removes the fixturing and welding operations, removes the weld inspection, and removes the tolerance stack-up that a multi-piece weldment carries.
Mass comes out through geometry rather than material substitution alone. Ribs at 60 to 80% of the adjoining wall thickness raise stiffness without adding a thermal mass that would trap porosity, and pockets are cored in during casting rather than milled out afterwards. The same die produces mounting bosses, cable clips, sensor pads and gasket grooves at effectively no incremental piece cost.
On cost, the die is a fixed investment of typically 3,000 to 25,000 USD that amortises across the programme, so above roughly 5,000 parts per year the piece price of a casting sits well below the machined equivalent — commonly 50 to 80% lower on parts with any geometric complexity. Multi-cavity tooling pushes that further on high-volume brackets and sensor bodies.
The parts below are representative of the automotive work that suits high pressure aluminum die casting: structural but not crash-critical, geometrically complex, and produced in volumes where tooling amortises quickly.
| Component | Alloy | Key requirement | Typical finish |
|---|---|---|---|
| EV battery module bracket | A380 | Stiffness at low mass, flatness across mounting pads, dimensional repeatability for module stack-up | Shot blast plus chromate conversion, powder coat where exposed |
| Sensor and camera housing | ADC12 | Thin wall, sealed cavity, machined connector bore, EMI shielding continuity | Shot blast, black powder coat, masked grounding pad |
| Coolant or oil pump body | A360 | Pressure tightness at the specified test pressure, machined sealing face and bearing bore | Shot blast, machined faces left bare |
| Transmission and gearbox cover | A380 | Flatness on the gasket face, thread strength, oil tightness | Shot blast, chromate conversion |
| Motor end cover and terminal box | A380 | Bearing bore concentricity, earth continuity, IP-rated sealing land | Powder coat with masked bore and grounding face |
| Inverter and power electronics housing | A360 | Heat dissipation through cast fins, flat interface for thermal paste, shielded enclosure | Shot blast, chromate conversion, machined thermal interface |
| Structural mounting bracket | A380 | Fatigue performance at bolted joints, machined datum surfaces, mass target | Shot blast plus powder coat |
| Lighting and lamp body | ADC12 | Thin wall, thermal path from the LED board, gasket groove for water sealing | Powder coat or wet paint |
We do not quote castings for crash structures, suspension links, steering components or other safety-critical load paths that require fatigue-validated cast material and an IATF-certified site.
A380 is the default because it machines well, casts reliably and costs the least, which matters on a price-walked programme. Switch to A360 when the part is pressure tight, wetted by coolant, or exposed to salt spray: its low copper content substantially improves corrosion resistance and pressure tightness, at the cost of slightly harder machining. ADC12 is the choice for thin-wall sensor and lighting bodies with long flow paths.
Structural brackets typically run 2.5 to 4 mm with ribs rather than a uniformly thick section, because a thick wall solidifies last, shrinks inward and leaves porosity exactly where a bolted joint is loaded. Sensor and lamp housings run 1.5 to 2 mm. We hold 1.5 mm as the routine minimum and 1.0 mm only on small parts with short flow paths.
As-cast features hold ±0.1 mm over the first 25 mm, widening across the parting line and slides. Critical characteristics on an automotive print are usually bolt-hole positions, sealing faces, bearing bores and datum pads, so those are machined to ±0.02 mm from cast datums while everything else stays as-cast. Deciding this feature by feature at DFM keeps machining time — and therefore price — off features that do not need it.
Dimensions within one die half hold tighter than dimensions spanning the parting line, so the sensor bore and its mounting flange belong on the same side of the die. Getting this wrong is the most common reason a print's geometric tolerance cannot be met without extra machining.
Underbody and engine-bay parts get chromate conversion coating, which protects against corrosion while leaving the surface electrically conductive for earth paths and giving powder coat something to adhere to. Powder coat over chromate is the standard system for exposed brackets. Anodizing is available but produces a darker, less uniform result on high-silicon die cast alloys, so we rarely recommend it for automotive.
Tapped holes in cast aluminum want a thread engagement of 1.5 to 2 times the diameter, and a boss thick enough to carry the torque without local porosity. Where a joint is opened and reclosed in service, we specify steel threaded inserts rather than relying on aluminum threads to survive repeated assembly.
Electrification has shifted the mix of aluminum castings we quote. Engine-adjacent parts have declined; battery, thermal management and power electronics parts have grown, and they bring different acceptance criteria.
Battery-side parts are larger, flatter and more sensitive to distortion because modules stack against them, so flatness across the mounting plane and consistent part-to-part geometry matter more than absolute wall thinness. Power electronics housings are judged on thermal performance, which means cast fin geometry, a machined flat interface for the thermal pad, and A360 or A413 for their higher thermal conductivity.
Electrical requirements also appear on the print. High-voltage enclosures need continuous conductive paths for shielding and earthing, so grounding pads are masked during coating or machined clean afterwards, and coating thickness on those faces becomes a controlled dimension rather than a cosmetic one.
Automotive quality is a paperwork discipline as much as a measurement discipline. We build the documentation package alongside the tooling rather than assembling it after the fact, because a PPAP submission that starts after the capability run is already late.
| Stage | What happens | Typical duration |
|---|---|---|
| Feasibility and DFM | Castability review, alloy recommendation, machining plan, flow simulation, written DFM report | 2 to 3 business days |
| Quotation and price walk | Piece price, tooling cost, cavity count options, packaging and freight assumptions | 1 to 2 business days after DFM |
| Tool design and manufacture | Die design, steel cut in H13, flow and solidification simulation, slide and cooling layout | 25 to 40 days |
| T1 samples | First shots, dimensional layout against print, DFM feedback on any die correction | 5 to 7 days after tooling |
| Sample approval and correction | Die adjustment, machining fixture proving, resubmission of dimensional results | 5 to 15 days |
| Capability run and PPAP | Consecutive-part run, Cpk on nominated characteristics, submission package compiled | 5 to 10 days |
| Production | Casting, machining, finishing, leak test, inspection and packing per release | 15 to 25 days per batch |
| Service and spares | Tooling stored and maintained on site, requalified with FAI after refurbishment | Life of the programme |
Repeat production releases on proven tooling ship in 15 to 20 days. Die refurbishment is scheduled against shot count, typically between 80,000 and 150,000 shots.
No. CharMax Precision is certified to ISO 9001:2015 only. We support automotive programmes as a Tier 2 or Tier 3 supplier inside a Tier 1 customer's quality system, or direct to an OEM under a customer-specific quality agreement, and we supply PPAP-format documentation, control plans, capability studies and IMDS data. What we cannot do is act as the IATF-certified site of record for a programme that requires one, so that requirement should be confirmed before sourcing rather than at audit.
Yes, in PPAP format and at the submission level your programme specifies. A typical Level 3 package from us includes the part submission warrant, design records and drawing revision, process flow diagram, PFMEA input, control plan, measurement system analysis on the gauges used, dimensional results, material and performance test results, initial process capability study, sample parts and a master sample retained on site. Tell us the submission level and the customer-specific requirements at quotation so the data is collected during the launch rather than reconstructed afterwards.
Yes. We provide full alloy chemistry from the spectrometer analysis, the ingot certificate, and the substance data for the coating system, then either submit the IMDS entry for our casting or hand the data to your materials team to enter under your account. Where a coating or insert comes from a sub-supplier, we obtain their declaration as part of the package. RoHS and REACH declarations are supplied on the same basis.
In most non-safety-critical brackets, yes, and the mass saving is typically 40 to 60% at comparable stiffness once the geometry is redesigned with ribs instead of plate thickness. The trade-offs are honest ones: high pressure die castings contain some entrapped gas, so fatigue performance is lower than wrought aluminum or steel and welding the casting is not advisable. For crash structures, suspension links, steering components and other fatigue-critical load paths, we recommend a different process and an IATF-certified source.
Pressure tightness is designed in at four points. A360 alloy is specified for its superior pressure tightness; gating, overflows and venting are laid out so the last metal to freeze is outside the sealed volume; vacuum assist is used where the geometry demands it; and sealing faces are machined after casting rather than relying on as-cast flatness. Every part is then air-decay leak tested to your stated pressure and leak rate, either 100% or to an agreed sampling plan, with results recorded per lot.
From roughly 5,000 parts a year the economics are clearly in favour of casting, and most automotive programmes sit far above that. Between 1,000 and 5,000 parts a year it depends on geometry: a thin-walled sensor housing with cast-in features still wins, while a simple flat bracket may be cheaper machined. Below about 1,000 parts a year, which is common for service-only parts, we will tell you if CNC machining from billet is the better answer.
Production tooling takes 25 to 40 days depending on part complexity and cavity count, followed by 5 to 7 days for T1 sample production. After you approve samples, production lead time is 15 to 25 days including machining, finishing and inspection. For repeat orders on existing tooling, expect 15 to 20 days.
Send your 2D drawing and 3D model, the annual volume, and the critical characteristics on the print. You will get piece pricing, tooling cost, a machining plan and a written DFM report, plus confirmation of exactly which PPAP elements we can supply.