Thermomechanical Treatment Influence on the High-speed Steel Hardness and Wear

摘要

Thermomechanical treatment consists in using two classic manufacturing methods. This type of treatment was applied to studied high-speed steel (HS2-9-1-8). The tests performed aimed to establish the influence on the hardness and wear of the high-temperature thermomechanical treatment (HTTMT) applied to studied steel. The application of an additional plastic deformation (the deformation degree between 45 – 75%) positively influences the hardness and wear value. Being a HTTMT, the plastic deformation was followed by quenching, the utilized agent being the oil or compressed air. When the quenching agent was the oil the hardness increased by 6-7% and the wear diminished up to 40%. Samples thermally treated in the classical way were used as comparison elements. The study performed shows that a favourable evolution of the analysed properties appears when the deformation degree is between 55 and 75%. The air compressed quenching sets for the analysed characteristics, the same evolution with those obtained during the oil quenching. The increased hardness for the studied high-speed steel utilized at cutting tools manufacturing will generate a slower wear of the cutting edge that means important economies in cutting process.