?? ?????? ????? ?????? ?????? ????? ????. ??? ?? ????? ???????? ??? ?????? ??????? ?????? HRC60. ?? ????? ?????? ?????? ???? ????? ???? ?????? 3-5 ???? ?? ???????? ???????. ??????? ?????? ?? ????? ????? ???????? ????? ??????? ??????? ?????? ????? ??????? ????? ?????????? ?? ?????? ????? ?? ????? ??????? ??? ??????? ?????? ??????? ?????????? ????????? ??????? ?????? ?????? ??????? ??????? ???? ??? ????? ????? ??????? ??? HRC58-HRC62? ????? ????? ?????? ?????? ??????? ??? ??????? ??? ???? ??????? ≤HRC32? ??? ??? ???? ??????? ?? ????? ??????? ???? ?????? ???? ?? ??? ????? ???????? ??? ???? (?? ??????) ?? ???? 5 ????? ??? ???? ??????? ?????????? ????? ?????????.