EN 10080 (EU) and GB/T 3078 (China) regulate cold-finished round bars with these key differences:
Dimensional tolerances: EN 10080 offers three classes (h7, h8, h9), with h7 providing ±0.01mm for 10mm diameter-tighter than GB/T 3078's ±0.01mm for premium grades.
Surface finish: EN specifies Ra ≤1.6 μm for h7 bars, while GB/T 3078 requires Ra ≤0.8 μm for mirror-finish applications, reflecting different industry priorities.
Straightness: EN 10080 mandates ≤0.3mm/m for precision bars, slightly stricter than GB/T 3078's ≤0.5mm/m.
Applications: EN 10080 h7 bars are used in EU medical devices, while GB/T 3078 bars dominate Chinese precision machinery, with both meeting their regional quality standards.