国产午夜一级,欧美三级午夜理伦三级在线观看,国产精品另类激情久久久免费,一级毛片免费高清,99精品黄色,日韩超级大片免费看国产国产播放器,亚洲精品日韩一区二区电影

Main Products
Products Grade: SCr420B
Specifications: φ16～38mm
Applied Standard: 
Characteristics: This product is used to produce high strength bolt of class 12.9.
Applications: Common partsCommon fastenerHigh strength fastener
Use of Products: SCr420B is a steel grade which used to produce high strength bolt of class 12.9 .This product has characteristics of uniform-chemical composition, low percentage of harmful elements, high purity, slight decarburisation, good surface quality. After spheroidize annealing, this product has the characteristics of good cold heading properties. And the product has excellent hardenability.