... and the hardness can be HRC48-52 after entirely normalizing , hardening and tempering . The impact can reach over 17J , thus it can improve ... theusability and wear resistance . We established a good reputation in ... , Komatsu, ESCO,JCB,Hyundai,Daewoo,Hitach,etcHeat treatment:Quenching and tempering treatment Hardness:Teeth : HRC48-52 ,Impact value >= ...