Aluminum 1050

Aluminum 1050 is a commercially pure aluminum alloy ideal for CNC machining of electrical, decorative, and corrosion-resistant parts where high conductivity, formability, and finish quality are required.

Introduction to Aluminum 1050

Aluminum 1050 is a commercially pure aluminum alloy with a minimum aluminum content of 99.5%. Known for its excellent electrical and thermal conductivity, superior corrosion resistance, and outstanding formability, Aluminum 1050 is one of the most widely used non-heat-treatable aluminum grades in both industrial and commercial applications.

In CNC machining, Aluminum 1050 is particularly suitable for components that require good aesthetics, conductivity, or easy forming, especially in the electrical, food, and chemical processing industries.

Chemical, Physical, and Mechanical Properties of Aluminum 1050

Chemical Composition (Typical)

Element	Composition Range (wt.%)	Key Role
Aluminum (Al)	≥99.5	Base element with high thermal and electrical conductivity
Iron (Fe)	≤0.40	Residual element
Silicon (Si)	≤0.25	Residual element
Copper (Cu)	≤0.05	Residual element
Zinc (Zn)	≤0.05	Residual element
Magnesium (Mg)	≤0.05	Residual element
Manganese (Mn)	≤0.05	Residual element
Others	≤0.03	Combined impurities

Physical Properties

Property	Value (Typical)	Test Standard/Condition
Density	2.71 g/cm³	ASTM B311
Melting Point	643°C	ASTM E299
Thermal Conductivity	229 W/m·K at 25°C	ASTM E1952
Electrical Conductivity	61% IACS at 20°C	ASTM B193
Coefficient of Expansion	24.8 µm/m·°C	ASTM E228
Specific Heat Capacity	900 J/kg·K	ASTM E1269
Elastic Modulus	69 GPa	ASTM E111

Mechanical Properties (H14 Temper)

Property	Value (Typical)	Test Standard
Tensile Strength	110 MPa	ASTM E8/E8M
Yield Strength (0.2%)	95 MPa	ASTM E8/E8M
Elongation	≥10%	ASTM E8/E8M
Hardness	35 HB	ASTM E10
Fatigue Strength	55 MPa	ASTM E466
Impact Resistance	High	ASTM E23

Key Characteristics of Aluminum 1050

Excellent Electrical and Thermal Conductivity: Aluminum 1050 boasts electrical conductivity of 61% IACS and thermal conductivity of 229 W/m·K, making it a top choice for heat exchangers, conductive bars, and thermal shields.

Outstanding Formability: The alloy’s softness enables deep drawing, spinning, and forming into complex shapes without cracking—ideal for chemical containers, food packaging, and architectural applications.

Superior Corrosion Resistance: Forms a natural oxide layer that resists corrosion in atmospheric and mildly acidic environments, suitable for outdoor, chemical, and food-grade components.

Low Mechanical Strength: With a tensile strength of only ~110 MPa, 1050 is unsuitable for structural loads but excellent for low-stress, high-ductility parts.

Non-Heat Treatable: Mechanical properties are improved by cold working rather than heat treatment. Available in various tempers such as O (annealed) and H14.

CNC Machining Challenges and Solutions for Aluminum 1050

Machining Challenges

Softness and Gumminess: Leads to poor chip breaking and surface smearing.
Built-Up Edge (BUE): Adhesion to cutting tools at low speeds or dull edges.
Risk of Surface Deformation: Prone to distortion under excessive clamping or force.

Optimized Machining Strategies

Tool Selection

Parameter	Recommendation	Rationale
Tool Material	Uncoated or DLC-coated carbide	Maintains sharp edges and reduces smearing
Geometry	Large rake angle, polished edges	Promotes clean cuts and chip control
Cutting Speed	250–450 m/min	Minimizes BUE and improves surface finish
Feed Rate	0.10–0.30 mm/rev	Supports dimensional accuracy and clean edges
Coolant	Dry or mist coolant	Prevents overheating and avoids oxidation

Aluminum 1050 Cutting Parameters (ISO 513 Compliance)

Operation	Speed (m/min)	Feed (mm/rev)	Depth of Cut (mm)	Coolant Pressure (bar)
Roughing	250–350	0.20–0.30	1.5–3.0	Dry or mist
Finishing	350–450	0.05–0.10	0.2–1.0	Mist cooling

Surface Treatment for Aluminum 1050 CNC Parts

Anodizing: Highly receptive to Type II anodizing for corrosion protection and decorative finish; oxide thickness ~5–25 µm.
Powder Coating: Offers excellent coverage and color customization with 60–120 µm thickness for wear and UV resistance.
Electropolishing: Achieves a smooth, reflective finish (Ra ≤0.2 µm) and enhances cleanliness for food-grade applications.
Passivation: Typically used as a pretreatment to remove contaminants and prepare for further coating.
Brushing: Produces Ra 0.8–1.6 µm finishes for signage, panels, and industrial interfaces.
Alodine Coating: Chromate conversion for corrosion resistance with conductivity retention in electrical parts.
UV Coating: Provides clear scratch and moisture resistance; typical thickness 5–15 µm.
Lacquer Coating: Used to preserve surface finish and improve appearance in consumer-facing aluminum components.