Cast aluminum alloy and aluminum window/door profile are routinely confused because both carry the word "aluminum," but the procurement categories, price units, and minimum order quantities diverge by an order of magnitude: cast aluminum blanks list at roughly US$2,900/ton with 1-ton MOQ [S2], while finished aluminum window/door systems are quoted at US$99-150 per square meter with 10 m² MOQ [S6][S5].
The decision is driven by geometry, structural load path, and surface treatment, not by alloy chemistry. Cast aluminum alloy covers complex 3-D industrial parts (housings, heat sinks, pump bodies) where mold cost is amortized over volume; aluminum window/door covers linear, hollow, thermal-break extrusions for the building envelope where extrusion die cost is amortized over profile length.
Material and Mechanical Baseline
Pure aluminum has a yield strength of 7-11 MPa; aluminum alloys span 200-600 MPa yield, and aluminum carries about one-third the density and one-third the stiffness of steel, which is why the same profile cross-section is so much lighter than a steel equivalent [S4]. This density gap is the single biggest reason aluminum window/door systems replaced steel frames in mid-rise residential and commercial envelopes, and also why cast aluminum replaced cast iron in portable equipment housings.
Cast aluminum alloys (typically A356, A380, ADC12) are poured or die-cast into near-net shapes; aluminum window/door profiles are almost always 6063-T5/T6 billets pushed through shaped dies, with a polyamide thermal-break strip co-extruded or knocked in for the insulation layer. The two processes share a base metal but diverge entirely in tolerance stack-up, surface finish expectation, and joining method. For readers who want the broader aluminum-alloy family tree, the aluminum-alloy grade and property reference lays out the wrought vs cast distinction cleanly.
Price, MOQ, and Lead-Time Comparison
On Made-in-China, Shandong Juli Aluminium lists aluminum fence/electrophoresis/thermal-break/window-and-door profiles at US$1.5-2.3/kg with 50 kg MOQ [S2], and Hehui General Equipment quotes finished aluminum windows and curtain-wall profiles at US$250/m² with 10 m² MOQ [S2]. A thermal-break horizontal sliding window from a Fujian OEM sits at US$99-129/m² with 10 m² MOQ [S6].
For cast aluminum blanks, Shanghai Bozhong Metal Group quotes US$2,900/ton with 1-ton MOQ for general aluminum extrusion/profile stock, and Yuxinyuntong in Tianjin prices thermal-break window profile stock at US$2.5/kg with 100 kg MOQ [S2]. Translating the per-ton cast-alloy figure: US$2,900/ton equals roughly US$2.9/kg, which is in the same per-kilogram band as window/door profile stock, but the MOQ, surface requirement, and tolerance class are different.
The decision matrix below lines the two categories up against four engineering criteria:
Geometry: cast aluminum = complex 3-D, undercuts, internal cavities; aluminum window/door = linear prismatic, hollow multi-chamber, possible thermal-break slot. Surface: cast aluminum = as-cast, shot-blasted, powder-coated, or anodized; window/door = anodized or powder-coated after thermal-break assembly, often with wood-grain film. Tolerance: cast aluminum = ±0.1-0.3 mm typical on machined features; window/door = ±0.05 mm on wall thickness for thermal-break profiles. Joining: cast aluminum = bolted, welded, or cast-in inserts; window/door = mechanical corner-cleat, crimped, or screw-port.
Process Route and Surface Treatment
Aluminum window and door accessories — handles, hinges, rollers — are largely die-cast or stamped zinc/aluminum alloy with powder-coat or electroplate finish. The Okorder aluminum-alloy door/window hinge spec lists the material as aluminum alloy, finish as powder coating or electroplated, color options white/black/silver, minimum order 200 pieces, monthly capacity 50,000 pieces, and 10-day delivery to Europe/Africa [S7]. Handle and roller pricing in the same category runs US$0.5-1.19/piece with 500-15,000 piece MOQs [S1].
For the main window/door frame itself, the dominant process is extrusion of 6063 billets through shaped dies, with thermal-break profiles using a 24-35 mm glass-fiber-reinforced polyamide strip pulled through a slot in the extrusion and knurled to lock mechanically. The EAH-series sectional profile family (spinning series EAH40/45/50/55/65, sliding series EAH80, EALM60) represents the standard Chinese profile depth ladder where the figure is the outer frame depth in millimetres [S3]. A wider frame generally means a deeper glazing pocket and better thermal performance.
Cast aluminum, by contrast, flows into a steel mold at 660-720 °C and solidifies under pressure (die casting) or gravity. The mold cost is high but the unit price drops sharply above 500-1,000 pieces. For reference, the cast-iron grade reference explains why cast iron, despite higher stiffness, loses to cast aluminum on weight-driven applications.
Application Fit: When to Pick Which
Choose cast aluminum alloy when the part is a 3-D industrial component (motor housing, gearbox cover, heat sink, pump body, lighting fixture, furniture joint) where complex geometry outweighs extrusion's cost advantage. Choose aluminum window/door system when the application is a building envelope element (window, sliding door, swing door, curtain wall, sunroom) where thermal-break profile, glazing pocket, and weather-stripping interface dominate the spec. [S2]
A common error is specifying cast aluminum for window frames to save cost; in practice, cast aluminum cannot deliver the thin, hollow, multi-chamber geometry that gives a window frame its thermal-break performance and torsional rigidity. Conversely, extruding a pump housing is impossible without machining billets from plate stock, which defeats the cost logic. The two are complementary, not substitutes. For spec-first procurement of envelope systems, the aluminum window and door system reference gives the cross-section family, glazing range, and hardware interface.
Standards, Certification, and Sourcing Channels
Picture-frame and casement window suppliers in Guangdong publish NFRC-certified thermal performance and on-time-delivery ratings; the Made-in-China catalog currently lists PA New Product customization systems at US$145.23-185.37/m² with 1 m² MOQ from Guangdong Baishan Furniture [S5]. NFRC certification matters for North American projects because it provides U-factor, SHGC, and air-leakage ratings that code officials accept; CE/EN 14351-1 is the European equivalent for window performance.
Supplier audit data matters as much as alloy grade: Guangdong Jinhuahai Aluminum (2,000+ m² plant, 101 employees, Foshan) supplies profiles and extrusions with OBM/OEM/ODM; Weifang Guanghe Metal Products holds ISO 9001:2015, ISO 14001, and ISO 45001:2018 certification and quotes US$2.2-3.5/kg with 10-50 kg MOQ for aluminum profile, extrusion, and window profile [S1][S2]. For system-level window/door selection — including thermal-break, screen-frame, and weatherstrip — the system-window-door reference maps profile depth, hardware channel, and glazing thickness together.
For comparison, the aluminum coil vs aluminum window & door procurement map sits in the same family and confirms that coil stock feeds downstream extrusion mills, which then feed window/door system fabricators — three distinct layers with three distinct MOQ and price bands.
Limitations, Failure Modes, and Common Pitfalls
Cast aluminum fails by shrinkage porosity (A356), hot tearing (A380 under high stress), and galvanic corrosion when joined to copper alloys without isolation. Aluminum window/door profiles fail by seal degradation at the polyamide thermal-break strip (typically 5-10 year service life depending on climate), by electrolytic corrosion at the steel screw-to-aluminum interface if stainless fasteners are not used, and by glazing-bead pop-out under wind load if the bead is undersized. [S4]
Both categories share the alloy-naming trap: a buyer asking for "aluminum alloy" without specifying cast vs wrought, temper (T5/T6), or profile depth ends up with the wrong product. Always lock the spec to process route (die-cast / sand-cast / gravity-cast / extrusion), temper, tolerance class, and surface treatment before comparing price.
Trackable signals for the next procurement cycle: 1) revised NFRC ratings for thermal-break casement systems from Guangdong and Fujian OEMs, published quarterly; 2) any ISO 45001 re-certification at Weifang Guanghe or Shandong Juli that would shift their MOQ bracket; 3) new CE/EN 14351-1 test reports on EAH80 sliding profiles, since EAH80 is the most common 80 mm sliding depth in Chinese export stock.