How to Control the Surface Finish of Polished Parts?

Controlling the surface finish of polished metal parts hinges on the coordinated optimization of the entire process, from material selection, processing technology, polishing methods to post-processing inspection. Here are the specific implementation paths:

Source Control: Material Selection and Pre-treatment

• Prefer high-purity raw materials: The fewer impurities in the material, the easier it is to achieve a high surface finish. For example, excessive Fe and Si content in aluminum alloys can lead to micropores, affecting the mirror finish.
• Strict pre-treatment: Removing oil, oxide layers, and burrs is fundamental. The hardened layer or residual stress layer after EDM must be removed through rough grinding to lay a good foundation for subsequent fine polishing.

Process Optimization

• Properly set cutting parameters: Control spindle speed, feed rate, and depth of cut to avoid surface damage caused by vibration or overheating. Using high-performance cutting fluid can effectively cool and remove chips, reducing micro-scratches.
• Tool Condition Management: Keep tools sharp and avoid "tool resistance"; chamfering of lathe tools should be rounded to improve surface texture continuity.

Post-processing and Quality Assurance

• Magnetic Abrasive Deburring: Suitable for hard-to-process areas such as internal holes and dead corners; deburring, polishing, and cleaning can be completed in 3-15 minutes.
• Anti-oxidation Protection: Immediately passivate or apply a protective film after polishing to prevent aluminum, copper, and other materials from oxidizing and losing their gloss in air.
• Strict Testing Standards: Use a surface roughness meter to measure the Ra value to ensure it meets design requirements; use a gloss meter to evaluate reflectivity; verify corrosion resistance through salt spray testing.