“…Therefore, there are difficulties in formulating steel selection criteria, hardening technology parameters, etc. These issues have always caused problems [55,56] and are still debatable in the drill bits manufacturing [2][3][4][5]. It is known [4] that steels are used for drill bits enterprises 'Hughes Christensen Co.', 'Smith International Inc.', 'Reed Tool Co.', 'Security DBS Dresser Industries Inc.', 'Varel Manufacturing Co.', etc.…”