scalling

If you are not washing your hair enough, greasiness can cuase a scalling problem which affects growth.

如果你不经常洗头发，油脂导致的结垢影响头发的生长。

Slab temperature variation entering the mill would be closely controlled, and exposure to air and consequent scalling would be minimized.

由于板坯进入轧机后温度受控制，暴露在空气的部位极少，因而化铁皮减少最低程度。