Choosing the appropriate CNC machining materials is a crucial step in ensuring the final performance, cost, and manufacturing feasibility of the parts. The decision-making process requires comprehensive consideration of multiple core factors, and the following is a systematic selection approach:
- Clarify the functional requirements of the parts (primary step)
This is the cornerstone of material selection. You need to ask yourself:
- Mechanical performance: How much stress, impact, or wear does the component need to withstand? Do you need high hardness, strength, or toughness?
- Working environment: Is it in a high temperature, low temperature, or corrosive environment (such as exposure to chemicals, seawater)? This determines the temperature resistance and corrosion resistance level of the material.
- Special performance: Do you require electrical/thermal conductivity, lightweight, magnetic properties, or food/medical grade biocompatibility?
- Evaluate the processability of the material
CNC machinability is directly related to production efficiency and quality.
- Easy to process materials: such as aluminum 6061, brass Delrin（POM）， They have low cutting resistance, slow tool wear, fast processing speed, good surface smoothness, and can significantly reduce processing time and cost.
- Difficult to process materials such as stainless steel, titanium alloys, and quenched tool steel have high hardness and strength, requiring lower cutting parameters, specialized tools, and coolant during processing, resulting in longer processing time and increased costs.
- Balancing cost-effectiveness
Material cost is an important component of total cost.
- Raw material prices: Ordinary steel is cheaper than aluminum alloy, but aluminum alloy has higher processing efficiency and may have lower total costs. Titanium alloys and superalloys are very expensive.
- Comprehensive cost: “Material cost+processing labor cost” needs to be calculated. An expensive material that is easy to process may have a lower total cost than a cheap material that is difficult to process.
- Consider subsequent processing and appearance
- Surface treatment: Aluminum is very suitable for anodizing (enhancing aesthetics and corrosion resistance), steel parts often require electroplating or blackening treatment, and plastics can be sprayed or silk screened. The selected material should be able to support the surface treatment process you expect.
- Appearance requirements: For visible parts, the texture and modifiability of the material itself are important.
Common material selection reference:
- Universal structure and lightweight application: Aluminum alloys (such as 6061, 7075) are the best choice, with high strength to weight ratio, easy processing, and moderate cost.
- High strength and wear resistance: Steel (such as low-carbon steel, stainless steel), suitable for structural components, shafts, and molds. Stainless steel (such as 304, 316) additionally provides excellent corrosion resistance.
- Special environment (high temperature/high strength): Titanium alloy, used for aerospace and medical implants, but with high processing difficulty and cost.
- Insulation, lightweight and wear-resistant: Engineering plastics (such as POM, nylon, PEEK), POM (Saigang) has excellent mechanical properties, nylon is tough, and PEEK is used in extreme environments with high temperature and high strength.
Material selection is a balancing art. It begins with functionality, refines with processing, and culminates in cost. It is recommended to communicate closely with Metalstar, detailing your application scenarios and budget. Based on our extensive experience, we can provide you with the most optimized material solution.