CNC Aluminium Machining Australia
Precision CNC machined aluminium components sourced Australia-wide. 6061-T6, 7075-T6, 2024, 5052, and more. Milling, turning, 5-axis machining. ISO 9001:2015. Quotes within 2 business days.
Aluminium Alloy Guide
Choosing the right aluminium alloy determines cost, machinability, strength, and surface finish options. Here is the complete guide to CNC aluminium alloys available in Australia.
6061-T6
Excellent machinability276 MPa tensile | Best for: General purpose structural, prototypes, most common choice
Best balance of machinability, strength, and corrosion resistance. Anodises well. Weldable. The default CNC aluminium.
7075-T6
Good machinability503 MPa tensile | Best for: Aerospace, defence, high-performance structural
Near-double the strength of 6061. Not weldable. More expensive. Specify only when higher strength is genuinely required.
2024-T3/T4
Good machinability470 MPa tensile | Best for: Aerospace (fatigue-critical), aircraft skin, fuselage frames
Excellent fatigue resistance. Poor corrosion resistance — always used with anodising or alodine. Classic aerospace alloy.
5052-H32
Good machinability228 MPa tensile | Best for: Marine environments, fuel tanks, pressure vessels
Best corrosion resistance of common alloys. Excellent in saltwater environments. Weldable. Not as strong as 6061.
6063-T5/T6
Excellent machinability186 MPa tensile | Best for: Extruded profiles, architectural, trim parts
Common in extrusions. Lower strength than 6061. Excellent surface finish for anodising. Cost-effective for simple shapes.
MIC-6 Cast Plate
Excellent machinability152 MPa tensile | Best for: Fixture plates, precision flat bases, tooling
Cast aluminium plate with exceptional flatness and dimensional stability. The choice for precision tooling plates and CMM fixtures.
Surface Finishes for Machined Aluminium
Anodising Type II
Electrochemical oxide layer 5–25μm. Available clear (silver) or in a range of colours including black, blue, red, gold. Increases corrosion resistance and hardness. Standard for most aluminium components.
- ✓ 5–25μm oxide layer
- ✓ Clear or coloured
- ✓ Mild corrosion resistance
- ✓ Standard industrial finish
Hard Anodising (Type III)
25–75μm dense oxide layer. Significantly harder than Type II (Vickers 400–600). Used for wear-resistant surfaces, hydraulic cylinders, and sliding components in aerospace and defence.
- ✓ 25–75μm dense oxide
- ✓ Wear-resistant surface
- ✓ Aerospace and defence
- ✓ Typically grey-black colour
Alodine / Chromate Conversion
Thin chemical conversion coating (0.5–4μm) that maintains electrical conductivity — unlike anodising which is non-conductive. MIL-DTL-5541 specification. Standard aerospace and electronics finish.
- ✓ Maintains conductivity
- ✓ MIL-DTL-5541 spec
- ✓ Iridescent gold appearance
- ✓ Aerospace standard
Powder Coating
Electrostatically applied polymer powder cured at 180–200°C. Wide colour range. Thicker than anodising (60–100μm), providing good impact and scratch resistance. Common for consumer and industrial products.
- ✓ Wide colour range
- ✓ 60–100μm coating
- ✓ Good impact resistance
- ✓ Consumer and industrial
Bead Blasting
Uniform matte surface texture by blasting with glass or ceramic beads. Often used prior to anodising for a consistent cosmetic appearance. Masks tool marks and minor surface defects.
- ✓ Uniform matte texture
- ✓ Pre-anodising preparation
- ✓ Masks tool marks
- ✓ Cosmetic improvement
As-Machined
CNC machined surface with visible tool paths. Ra 0.8–3.2μm depending on toolpath and stepover. Functional for most engineering applications without secondary finishing cost.
- ✓ Ra 0.8–3.2μm
- ✓ Lowest cost option
- ✓ Functional engineering finish
- ✓ No lead time addition
Design Tips for CNC Aluminium Parts
Minimum wall thickness 0.8mm
Aluminium is stiff enough to allow thin walls, but below 0.8mm vibration and distortion become problems. For tall thin walls, 1.5mm is more practical.
Standard thread sizes save cost
Use standard metric thread sizes (M3–M20). UNC/UNF available at no extra cost. Avoid custom thread forms.
Specify anodising before finish machining
Anodising adds 5–25μm per surface. For tight-tolerance bores and fits, machine after anodising or allow for the coating in your tolerances.
Favour radii over sharp internal corners
Sharp internal corners require slow machining passes or EDM. A 1mm internal radius adds no cost; sharp corners add significant cost.
Orient deep pockets for tool access
Deep pockets (depth > 3× width) require long-reach tooling and slower feeds. Redesign to 3:1 depth-to-width ratio where possible.
Standard stock sizes reduce material cost
Design to fit within standard aluminium stock sizes. 6061-T6 plate is cheapest in 25mm, 38mm, 50mm, 75mm thicknesses across Australia.
Aluminium Machining FAQ
Why is aluminium the most common CNC machining material?
Aluminium is the most widely CNC machined material for several key reasons: exceptional machinability (cuts 3–5x faster than steel, extending tool life), excellent strength-to-weight ratio (7075-T6 rivals mild steel at one-third the weight), good corrosion resistance without surface treatment, wide range of alloys for different applications, and availability across Australia in standard stock sizes. For prototyping and production parts where weight, cost, and machinability are priorities, aluminium 6061-T6 is almost always the first choice.
What is the difference between 6061 and 7075 aluminium?
6061-T6 is the most common general-purpose aluminium alloy. It offers good strength (276 MPa tensile), excellent corrosion resistance, weldability, and machinability. It anodises well and is suitable for structural, aerospace, and consumer applications. 7075-T6 is a high-strength aerospace alloy with approximately double the strength of 6061 (503 MPa tensile). It is used where maximum strength-to-weight ratio is required: aircraft structures, high-performance sporting goods, and defence components. 7075 is harder to machine than 6061, does not weld well, and is more expensive. Choose 6061 for most applications; specify 7075 only when the higher strength is genuinely needed.
What aluminium alloys are available for CNC machining in Australia?
Commonly stocked aluminium alloys for CNC machining in Australia include: 6061-T6 (most common — general structural, prototypes), 7075-T6 (aerospace and high strength), 2024-T3/T4 (aerospace, high fatigue strength), 5052-H32 (marine, excellent corrosion resistance, formable), 6063-T5/T6 (extrusions, architectural), 2011-T3 (free-machining, the easiest to machine of all aluminium alloys), 5083 (marine and pressure vessels), and MIC-6 cast tooling plate (extremely flat, dimensionally stable for fixturing and precision plates). Exotic alloys such as 7050 and 2219 are available on special order.
What surface finishes are available for CNC machined aluminium parts?
CNC machined aluminium can be supplied in many surface finishes: as-machined (Ra 1.6–3.2μm), bead blasted (uniform matte texture, Ra 1.6–3.2μm), anodising Type II (clear or coloured, 5–25μm oxide layer, corrosion protection), anodising Type III hard anodise (25–75μm, wear-resistant, engineering applications), alodine/chromate conversion (thin, maintains conductivity, aerospace standard), powder coating (decorative and protective, wide colour range), and electroless nickel plating (uniform coating, corrosion and wear resistance). Anodising is the most common secondary finish for CNC machined aluminium in Australian industry.
What tolerances can be held on CNC machined aluminium?
Aluminium machines to tighter tolerances more readily than most other metals due to its dimensional stability during cutting. Standard CNC machining: ±0.1mm. Precision machining: ±0.01mm. Tight tolerance with CMM verification: ±0.005mm. Aluminium's low density means less thermal distortion during machining and better stability than steel for thin-wall features. For critical aerospace and defence applications, aluminium is often specified precisely because it holds tolerances reliably in CNC machining.
What industries use CNC machined aluminium parts in Australia?
CNC machined aluminium is used across aerospace (structural components, brackets, housings), defence (vehicle components, weapon system parts, communications equipment), mining (lightweight housings, conveyor components, instrumentation enclosures), automotive (performance parts, suspension components, intake manifolds), electronics (heat sinks, enclosures, chassis), medical devices (equipment housings, fixture components), marine (deck hardware, winch components, instrument housings), and robotics and automation (robot arms, end effectors, linear motion components).
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