STUDY ON A NEW TECHNIQUE FOR CHROMIZING AND BORON-CHROMIUM, BORON-VANADIUM, BORON-TITANIUM, BORON-NIOBIUM CO-CEMENTATION BY HIGH FREQUENCY INDUCTION HEATING

摘要

Comparing with the conterparts with furnace heating, the rate of chromizing and boron-chromium, boron-vanadium, boron-titanium, boron-niobium co-cementation utilizing induction heating can be increased by 30 times and the electrical energy and cementation agent can be saved by 20%-50%. The distortion of workpieces is decreased obviously, and the cementation agent exhibits great capability of self-protection and the workpieces can be heated in air, so a sealed box or protective atmosphere is unnecessary, and the workpieces will not be oxidized and decarburized, moreover, the rating of surface finish will not be decreased. When a directional sleeve for rotary pressing was treated utilizing this technique, the durability of 45 steel chromized by high frequency induction was 5 times more than that of Crl2 steel after conventional quenching and tempering. When a honeycombing coal jumper bar made from 45 steel was treated with co-cementation by boron-chromium, boron-vanadium, boron-titanium and boron-niobium utilizing induction heating, the durability was 3 times more than that by conventional heat treatment.