CNC (Control numérico por computadora) machining relies heavily on the right choice of metal materials to achieve high precision, durabilidad, y rendimiento. Different metals have unique properties that make them suitable for specific industries—from aerospace to electronics, medical devices to automotive. Below is a detailed breakdown of the most common metal materials for Mecanizado CNC, their key traits, aplicaciones, and selection guidance.
1. Key Properties of Common CNC Machining Metals (Comparison Table)
To quickly compare core characteristics, here’s a summary of 10 widely used metals:
| Metal Material | Densidad (gramos/cm³) | Strength Level | Machinability | Resistencia a la corrosión | Rango de costos |
| Aleación de aluminio | 2.7 | Medio-alto | Excelente | Bien | Low-Medium |
| Acero inoxidable | 7.9 | Alto | Poor | Excelente | Medio |
| Carbon Steel | 7.85 | Alto | Average | Poor (needs coating) | Bajo |
| Cobre & Alloys | 8.9 | Low-Medium | Bien | Bien | Medio |
| Titanio & Alloys | 4.5 | muy alto | Very Poor | Excelente | muy alto |
| Nickel-Based Alloys | 8.1-8.5 | muy alto | Very Poor | Excelente | muy alto |
| Magnesium Alloy | 1.8 | Medio | Bien | Poor (needs coating) | Medio |
| Tungsten Steel (Carbide) | 14.0-15.0 | Extremely High | Very Poor | Excelente | Alto |
| Zinc Alloy | 6.6-6.9 | Bajo | Excelente | Bien | Bajo |
| Beryllium Copper | 8.25 | Alto | Bien | Bien | Alto |
2. Detailed Breakdown of Common Metals (with Models & Aplicaciones)
Each metal material has distinct advantages and ideal use cases. Below is a linear breakdown of their properties, popular models, and real-world applications:
2.1 Aleación de aluminio
Why choose it? It is the most widely used material in CNC machining due to its ligero (1/3 the density of steel) y excelente maquinabilidad—tools stay sharp longer, and complex parts (like aircraft frames) can be produced efficiently.
Key models:
- 6061: Heat-treatable, with balanced strength and weldability (used for automotive parts, cajas electrónicas).
- 7075: Ultra-high strength (5x stronger than 6061) for high-stress scenarios (componentes aeroespaciales, cuadros de bicicleta).
- 5052: resistente al óxido, ideal for marine or chemical equipment parts.
2.2 Acero inoxidable
Why choose it? Its superior corrosion resistance makes it indispensable for harsh environments (p.ej., saltwater, quimicos). Sin embargo, its high hardness leads to fast tool wear, requiring specialized cutting tools.
Key models:
- 304: General-purpose (food machinery, electrodomésticos de cocina) due to good rust resistance.
- 316: Added molybdenum for enhanced corrosion resistance (marine parts, implantes medicos).
- 17-4PH: Martensitic stainless steel that hardens with heat treatment (valvulas, zapatillas).
2.3 Carbon Steel
Why choose it? It offers high strength at a low cost, making it a budget-friendly option for structural parts. The downside? It rusts easily—so surface treatments (galvanoplastia, cuadro) are a must.
Key models:
- Q235: Ordinary structural steel (paréntesis, frames for industrial machines).
- 45# Acero: High-quality carbon steel (after quenching/tempering, used for gears, ejes).
- C45: European standard equivalent to 45# Acero (versatile for mechanical parts).
2.4 Other Essential Metals
- Cobre & Alloys: Sin par electrical/thermal conductivity (used for heat sinks, conectores electricos). Popular models: T2 pure copper (wires), H62 brass (plumbing fittings).
- Titanio & Alloys: El “aerospace metal”—alta resistencia + ligero (used for jet engine parts, implantes medicos). Key model: Ti-6Al-4V (most widely used titanium alloy).
- Zinc Alloy: Punto de fusión bajo, ideal for die-casting (juguetes, piezas decorativas). Common model: las cargas 3 (good fluidity).
3. How to Select the Right Metal for CNC Machining?
Choosing the wrong material wastes time and money. Follow this 3-step guide to match your needs:
Paso 1: Prioritize Application Requirements
- Need ligero + fortaleza? Choose aluminum alloy (aerospace/automotive) or titanium alloy (high-end medical).
- Need conductividad? Copper alloys (electrónica, disipadores de calor) are unbeatable.
- Need resistencia a la corrosión? Acero inoxidable (316 for marine) or nickel-based alloys (extreme temperatures).
Paso 2: Consider Machinability
- Easy-to-machine materials (aluminio, cobre, zinc): Best for complex parts (p.ej., 3C product casings) because they reduce tool costs and production time.
- Difficult-to-machine materials (acero inoxidable, titanio): Require high-precision CNC machines and coated tools—use only for high-stress or harsh-environment parts (p.ej., implantes medicos).
Paso 3: Balance Cost
- Low-cost options: Carbon steel (structural parts), aleación de aluminio (general components).
- High-cost options: Titanium alloy (aeroespacial), nickel-based alloys (gas turbines)—reserve for applications where performance is non-negotiable.
4. La perspectiva de la tecnología Yigu
En Yigu Tecnología, we believe the success of CNC machining starts with material selection. Over the years, we’ve supported clients in aerospace, médico, and automotive industries by matching them with optimal metals—for example, using Ti-6Al-4V for lightweight medical implants and 6061 aluminum for cost-effective automotive parts. We also invest in advanced cutting tools (p.ej., carbide tools for stainless steel) to overcome machinability challenges. For clients, the goal isn’t just to “machine a part”—it’s to choose a material that maximizes performance while controlling costs. We recommend starting with a clear list of application needs (fortaleza, ambiente, presupuesto) to narrow down options quickly.
5. Preguntas frecuentes (Frequently Asked Questions)
- Q: Which metal is best for CNC machining complex, piezas ligeras?
A: aleación de aluminio (p.ej., 6061) is ideal—it has excellent machinability for complex shapes and is lightweight, making it perfect for electronics or automotive components.
- Q: Do I need surface treatment for carbon steel in CNC machining?
A: Sí. Carbon steel has poor corrosion resistance, so surface treatments like electroplating (for rust protection) or painting (for aesthetics) are required to extend the part’s lifespan.
- Q: Why is titanium alloy more expensive than other metals for CNC machining?
A: Titanium alloy has very high strength and corrosion resistance, but it is extremely difficult to machine—tools wear out quickly, and production takes longer. These factors (material cost + tiempo de mecanizado) drive up the overall cost.
