Induction hardening process capable of hardening hard-alloy cast iron camshaft

• Main Authors: DENG WEILIN, LIU JUNKAI
• Format: Patent
• Language: Chinese; English
• Published: 19.09.2012
• Subjects: CHEMISTRY; CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION ORPROCESSING OF GOODS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUSMETALS OR ALLOYS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; MAKING METAL MALLEABLE BY DECARBURISATION, TEMPERING OR OTHERTREATMENTS; METALLURGY; METALLURGY OF IRON; MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINSTCLIMATE CHANGE

The invention provides an induction hardening process capable of hardening a hard-alloy cast iron camshaft. The induction hardening process comprises the following steps of: firstly, preheating the camshaft and inductively heating the preheated camshaft to 810-850DEG C at the heating speed of 60-70DEG C/second; secondly, inductively heating the preheated camshaft to 900-940DEG C at the heating speed of 60-70DEG C/second; hardening the camshaft by adopting compressed air for 35-50 seconds; cooling the camshaft to 240-310DEG C, wherein the pressure of the compressed air is 0.38-0.52MPa; and finally, standing the hardened camshaft at room temperature for 50-60 minutes and finishing tempering by using residual temperature after hardening. According to the induction hardening process, the defects in the prior art are overcome and the cracking rate after process hardening can be greatly reduced on the premise that the requirement on the quenching technology is met, so that the production cost is greatly reduced.