Induction surface hardening of 42CrMo4 steel tubes designed for rotary percussive drilling equipment

Abstract

42CrMo4 steel tubes are subjected to multiple induction heat treatments to obtain various hardened layer depths after spray water quenching. Current frequency, induction unit power and coil movement velocity along the tube axis are under consideration. The hardened layer depth is estimated along the transverse direction of the tubes using metallographic studies and microhardness measurements. An empirical equation is obtained for the hardened layer depth as a function of the induction heat treatment parameters. The laboratory test results are employed to develop the technology of the production of 42CrMo4 steel tubes designed for rotary percussive drilling equipment. The service life of induction hardened tubes during abrasive wear resistance field tests is approximately twice as long as that of conventionally nitrided ones. © 2016 Author(s).