Troubleshooting Uneven Hardness in Recycled Copper Planishing
再生铜板打平硬度不均的排查
标签：再生铜, 硬度不均, 偏析, 网格测点, 局部退火
再生铜轧板常因成分偏析，打平后表面硬度不均（偏差 HV 20–40），锤痕深浅不一、局部回弹大。排查：①用便携硬度计按 30 mm 间距网格测点，画出硬度分布图；②对高硬区做局部退火（650 ℃×8 min）而非整板退火；③若反复出现橘皮说明偏析严重，换批或加一道 10% 冷轧+退火匀化。记录每批料硬度基线以定锤击力度。
Recycled rolled copper often shows composition segregation, giving uneven hardness after planishing (HV spread 20–40): inconsistent marks and patchy springback. Check: (1) map hardness on a 30 mm grid with a portable tester; (2) locally anneal hard zones (650 °C × 8 min) instead of the whole sheet; (3) recurring orange-peel means severe segregation—change batch or add a 10% cold roll plus anneal to homogenise. Log a hardness baseline per batch to set hammer force. ---