کنترل کیفیت

I. Raw Material Quality Control

• Strict substrate selection: Prioritize 304/316 grade stainless steel sheets. The substrate surface must be free of scratches, pitting, and corrosion, with a flatness error ≤0.3mm/m. Request factory material certificates (e.g., spectral test reports) during procurement.
• Standardized substrate pre-treatment: Conduct three-step cleaning (degreasing, pickling, passivation) before processing to remove surface oil and oxide scale, avoiding impurities that affect coloring adhesion. The coloring process must be initiated within 24 hours after pre-treatment.

II. Coloring Process Control

• Unified process parameters: For PVD vacuum coating or electrolytic coloring, fix core parameters such as temperature (±2℃), voltage (±0.5V), and time (±5min). Conduct sample testing before producing different batches to ensure color consistency with the standard color chip.
• Clean environment control: Maintain a constant temperature (20-25℃) and humidity (40%-60%) in the coloring workshop to prevent surface pinholes and color differences caused by dust and moisture. The vacuum degree in the coating chamber must be stably maintained above 10⁻³Pa.

III. Surface and Performance Quality Control

• Appearance defect inspection: Finished products must pass manual visual inspection (or machine vision inspection). Requirements include uniform color without shade variation, no scratches, bubbles, or coating peeling on the surface, and consistent, unbroken, non-reversed random/brush textures.
• Key performance testing:
  • Adhesion test: Use a cross-cut tester to create a 1mm×1mm grid, with no coating peeling after tape adhesion.
  • Corrosion resistance test: Neutral salt spray test for ≥48 hours, with no rust or discoloration on the surface.
  • Anti-fingerprint test: After applying sebum, wipe with a dry cloth—no residual marks and easy to clean.

IV. Finished Product Factory Inspection and Traceability

• Sampling inspection standards: Sample 3% of each batch, covering dimensional tolerances (thickness ±0.05mm, width ±2mm), color difference (ΔE≤1.5), and performance indicators. Unqualified batches require full inspection and rework.
• Establish a traceability system: Mark each batch with a production lot number, linking it to raw material batches, process parameters, and test reports to facilitate subsequent quality traceability and recall.