Precision Begins with the Right Material and Process
In precision manufacturing, CNC Turning is a core technology for high-efficiency, repeatable, and high-accuracy production. With increasing demands on part strength, corrosion resistance, visual quality, and cost control, selecting the right material and matching it with the proper surface treatment is critical.
This guide provides a deep dive into the most widely used materials and finishing processes for CNC turning parts, from their machining properties to real-world applications.
1. Common Materials Used in CNC Turning
CNC Turning is suitable for metal and selected engineering plastic materials. Each type has its own characteristics that affect cutting performance, part precision, and end-use functionality.
🔩 Metal Materials
1. Aluminum Alloys (6061, 7075)
- ✅ Advantages: Lightweight, corrosion-resistant, excellent machinability
- 🎯 Applications: Aerospace parts, structural brackets, consumer electronics, lighting housings
- ⚖️ Notes: 7075 offers higher strength but comes with a higher cost
2. Stainless Steel (303, 304, 316)
- ✅ Advantages: High strength, excellent corrosion and heat resistance
- 🎯 Applications: Fasteners, medical tools, pump bodies, flanges, valves
- ⚖️ Notes: 304 is versatile; 316 is preferred for marine or chemical environments
3. Brass (C3604)
- ✅ Advantages: Excellent conductivity and machinability
- 🎯 Applications: Electrical connectors, valves, decorative parts
- ⚖️ Notes: Ideal for precision threaded parts
4. Carbon Steel (1018, 1045)
- ✅ Advantages: High strength and low cost
- 🎯 Applications: Shafts, fixtures, machine components
- ⚖️ Notes: Needs surface protection like black oxide to prevent rust
5. Titanium Alloy (Ti6Al4V)
- ✅ Advantages: Lightweight, ultra-strong, corrosion-resistant, biocompatible
- 🎯 Applications: Aerospace, medical implants, defense parts
- ⚖️ Notes: Difficult to machine and more expensive
🛠️ Engineering Plastics
1. POM (Delrin)
- ✅ Excellent strength, wear resistance, self-lubricating
- 🎯 Applications: Gears, bushings, sliders, housings
2. PTFE (Teflon)
- ✅ High chemical and heat resistance, self-lubricating
- 🎯 Applications: Seals, gaskets, chemical components
3. Nylon (PA6/PA66)
- ✅ Tough and impact-resistant
- 🎯 Applications: Pulleys, brackets, insulation parts
2. Common Surface Finishing Options
After CNC Turning, surface finishing improves the appearance, durability, corrosion resistance, and tactile feel of parts. Surface treatments fall into three main categories:
🎨 A. Aesthetic Finishes
| Process | Suitable Materials | Features | Visual Result |
|---|---|---|---|
| Anodizing | Aluminum | Enhanced corrosion resistance, color options | Matte, black/silver/red/blue, etc. |
| Brushed Finish | Aluminum, Stainless Steel | Elegant textured lines | Silver, titanium gray, etc. |
| Sandblasting | Most metals | Smooth matte texture, removes burrs | Uniform matte finish |
🛡️ B. Protective Finishes
| Process | Materials | Features | Application |
| Passivation | Stainless Steel | Boosts corrosion resistance, no color change | Medical, outdoor parts |
| Electroplating | Brass, Steel | Visual appeal, corrosion resistance, conductivity | Nickel, chrome, gold plating |
| Black Oxide | Carbon Steel | Anti-rust, anti-glare, wear-resistant | Industrial/mechanical components |
🔥 C. Heat Treatments
| Process | Materials | Effect |
| Quenching & Tempering | Carbon Steel | Improves hardness and impact resistance |
| Surface Nitriding | Alloy Steel | High surface hardness, tough core |
| Solution Treatment | Stainless Steel | Better strength and corrosion resistance |
3. Material + Finish Pairing Recommendations
| Product Requirement | Ideal Combination |
| High precision + aesthetics | 6061 Aluminum + Anodizing + Brushed Finish |
| Strength + corrosion resistance | 304 Stainless Steel + Passivation |
| Conductivity + appearance | Brass + Nickel Plating |
| Industrial durability + low cost | 1045 Carbon Steel + Black Oxide |
4. What We Offer
✅ Wide inventory of metals and plastics (Aluminum, Stainless Steel, Brass, POM, etc.)
✅ Full finishing options (anodizing, plating, brushing, heat treatment)
✅ Surface roughness control to Ra 0.8 or finer
✅ Small-batch prototyping and full-scale production available
📂 Upload your CAD drawings (STEP/DWG/IGES) for a free material + process consultation and quote!
