GB/T 30789.4-2015
色漆和清漆 涂層老化的評價 缺陷的數量和大小以及外觀均勻變化程度的標識 第4部分:開裂等級的評定
Paints and varnishes.Evaluation of degradation of coatings.Designation of quantity and size of defects,and of intensity of uniform changes in appearance.Part 4:Assessment of degree of cracking
GBT30789.4-2015, GB30789.4-2015