Что делает обработку поверхности с ЧПУ незаменимой для точного производства?

In modern precision manufacturing, from automotive engine blocks to aerospace titanium alloy frames, CNC surface reduction machining stands out as a core process. Unlike ordinary rough machining that prioritizes speed, it focuses on controlled material removal to achieve exact geometries, Точность размеров, and surface integrity. This article breaks down its core goals, key implementation steps, parameter controls, and practical applications to help you master this critical technique.

1. What Are the Core Goals of CNC Surface Reduction Machining?

The primary value of this process lies in “correction” and “optimization” rather than just material removal. Below are its four core objectives, organized by practical priority:

2. How to Choose Equipment and Tools for CNC Surface Reduction Machining?

Правильное сочетание станков и инструментов напрямую влияет на точность и эффективность обработки.. Ниже приведено подробное руководство для различных типов заготовок.:

2.1 Machine Tool Selection Based on Workpiece Size

2.2 Tool Selection Based on Material Characteristics

3. What Programming Strategies Optimize CNC Surface Reduction Machining?

Poor programming leads to tool marks, uneven cutting loads, and low efficiency. Ниже 4 проверенные стратегии оптимизации:

1. Spiral Progressive Cutting Depth

Replace vertical up/down tool entry with spiral feeding (helix angle: 10-15°). This reduces cutting impact by 40% and avoids sudden tool breakage.

2. Reasonable Overlap Rate Setting

Maintain an overlap rate of 15%-30% between adjacent toolpaths. Например, а 20% overlap for a φ 10mm cutter ensures no uncut areas and smooth surface transitions.

3. Island Boss Path Planning

For workpieces with island bosses (НАПРИМЕР., engine cylinder heads), use loop cutting (from outside to inside). This balances tool load (fluctuation ≤ 10%) and prevents tool deflection.

4. Cycloidal Tool Path Generation

Используйте программное обеспечение CAM (НАПРИМЕР., и, Мастеркам) to generate cycloidal paths. This reduces tool marks by 60% compared to linear paths and improves surface roughness from Ra 1.6μm to Ra 0.8μm.

4. How to Control Process Parameters for High-Quality Results?

Parameter mismatches are the top cause of defects (НАПРИМЕР., surface burns, отклонения размеров). Ниже приведено руководство по параметрам для распространенных материалов.:

4.1 Key Parameters for Different Materials

4.2 Cooling Strategy for Difficult-to-Machine Materials

Для нержавеющей стали или титанового сплава, увеличить поток охлаждающей жидкости, чтобы 15-20 L/мин (использование хлорсодержащих противозадирных присадок). Это снижает температуру резания на 50°C и предотвращает нагартование..

5. How to Prevent Deformation and Ensure Quality?

Тонкостенные детали и материалы высокой твердости склонны к деформации.. Ниже 3 критические меры обеспечения качества:

5.1 Stress Deformation Prevention for Thin-Walled Parts

• Используйте послойную резку: Каждая глубина резания ≤ 20% толщины стены (НАПРИМЕР., 0.4мм макс. для детали толщиной 2 мм.).
• Separate roughing and finishing: Add an aging process between them to release internal stress (reduces deformation by 70%).
• Optimize clamping: Use a multi-point support fixture (support area ≥ 80% of workpiece bottom) to avoid single-point stress concentration.

5.2 Geometric Tolerance Inspection

• Use a magnetic base dial indicator (точность: 0.001мм) for multi-point flatness checks (≥ 5 measurement points per m²).
• For large surfaces, detect diagonal height differences (max allowable: 0.03М-м-м) Чтобы предотвратить деформацию.
• Используйте координату измерительную машину (ШМ) for full-profile inspection of precision parts (detection accuracy: ± 0,002 мм).

6. Yigu Technology’s Perspective on CNC Surface Reduction Machining

В Yigu Technology, Мы видим CNC surface reduction machining as a “precision correction tool” rather than a simple cutting process. Our data shows that 60% of precision part failures stem from improper machining strategies—for example, using linear tool paths on thin-walled parts causes 30% more deformation than cycloidal paths.

We recommend integrating machining requirements into the early design stage: For auto engine blocks, we combine PCD cutters with spiral cutting to achieve Ra 0.4μm surface roughness; for aerospace titanium frames, we use gantry machines with multi-point clamping to control flatness within 0.02mm/m. By balancing efficiency and precision, we help customers reduce rework rates by 25% and improve production efficiency by 30%.

7. Часто задаваемые вопросы: Common Questions About CNC Surface Reduction Machining

1 квартал: Can CNC surface reduction machining correct pre-process errors?

Да. It can fix errors like uneven thickness (up to 0.1mm) or local dents from casting/forging. Например, it can repair 0.05mm deep dents on mold parting surfaces to restore sealing performance.

2 квартал: What’s the difference between CNC surface reduction and ordinary rough machining?

Ordinary rough machining prioritizes material removal speed (removal rate ≥ 100 cm³/min) with low accuracy (терпимость: ± 0,1 мм). CNC surface reduction focuses on precision (терпимость: ± 0,01 мм) и качество поверхности (Ra ≤ 0.8μm), с более медленной скоростью удаления (10-50 cm³/min).

Q3: How to handle high-hardness quenched steel (HRC ≥ 50) in this process?

Используйте технологию резки с вибрацией. (частота вибрации: 20-50 кГц) уменьшить силу резания за счет 40%. Сопоставьте это с CBN (Кубический нитрид бора) инструменты (твердость: СПЧ 70-80) во избежание износа инструмента и обеспечения чистоты поверхности.