split washer

　　Strength: 430-510HV Material: Carbon steel, alloy steel

　　Material: 65Mn

　　Material Description: 65Mn Spring Steel Chemical Composition: Carbon C: 0.62~0.70 Silicon Si: 0.17~0.37 Manganese Mn: 0.90~1.20 Sulfur S: ≤ 0.035 Phosphorus P: ≤ 0.035 Chromium Cr: ≤ 0.25 Nickel Ni: ≤ 0.30 Copper Cu: ≤ 0.25 Fold and edit the hardness of this paragraph Hot rolled hardness: 240~270HB Cold rolled soft hardness: 190~220HB Cold rolled hard hardness: 300~340HB Heat treated hardness: 38~60HRC

　　Surface treatment: Blackening (quenching)

　　Surface treatment content: Blackening is a common method of metal heat treatment, which is to create a layer of oxide film on the metal surface to isolate air and achieve the purpose of rust prevention. When the appearance requirements are not high, blackening treatment can be used, and the surface of steel parts can be blackened, also known as bluing.