The color of the products is argent grey metallic shine, smooth, unknit. They mustn't be oxydic badly, lacking of sintering, over heating, delamination and cracking.

产品表面呈银灰色金、滑、平整、有严重氧化现象，有欠烧、过熔、鼓泡、分层、裂纹等缺陷。