High speed steel tool heat treatment method

The invention relates to a high speed steel tool heat treatment method and the method specifically includes the following steps: high-temperature step quenching steel materials to be treated in a quenching medium at the temperature of 1200-1310 DEG C; after quenching, cooling to room temperature and then low-temperature tempering for 1h at the temperature of 80-100 DEG C; cold treating for 2-3h at the temperature of minus 120-minus 80 DEG C; and finally tempering for 1-1.5h at the temperature of 540-560 DEG C, wherein the quenching medium is selected from calcium chloride saturated water solution, polyglycol water solution, polyving akohol water solution or potassium permanganate quenching liquid. The high speed steel tool heat treatment method is simple in process and saves energy, and compared with traditional technology, the mechanical performance and service life of the high speed steel tool are improved by around 20-40 percent.