... steel flat bar 1) Grade: Alloy steel flat bar 42CrMo, 4140, 40Cr 2) Specification: 10-120mm * 200 ... -rolled,black surface ,Hardness: ≤220HB.2) Chemical composition:C=0.41~0.45, Cr=0.99-1 ... According to the customer's requirement of Chemical Composition, Physical Properties and Mechanical Testing7.Test: ultrasonic test ... manufacturer LOGO and weight (kg) is painted. 42CrMo,4140,40Cr alloy steel flat bar