Speaker
Description
Manufacturing industry is one of the world leading industries, as its end products (tools, gears, bearings, shafts, beams, bolts etc.) influence our everyday life. The performance of used metallic materials and products is subjected to the selection of steel type (main alloying elements), proper design, manufacturing accuracy and application of proper heat treatment. One of the options is deep cryogenic treatment (DCT; temperature below -160 °C), whose implementation in industry has emerged in the last years, despite its long history. Hot work tool steels, which were selected for detailed investigation of DCT effect are AISI H11, AISI H13 and AISI H21, showing certain differences in the chemical composition. For selected group of tool steels, study showed that DCT also induces precipitation of different types of carbides by 56 %, M23C6, by 25 % M7C3 and as well M6C carbides by 28 %. This additionally indicates the complex DCT mechanism, which does not universally modify all ferrous alloys in the same manner, but is strongly related to characteristics of each ferrous alloy. DCT induced also the transformation of retained austenite into martensite in hot work tool steels. DCT induced also a finer homogenous microstructure of bainite and martensite, with preferable orientation of martensite along [101] and [001] directions. Temperature effect of heat treatment in correlation to DCT performance showed that subgroups with higher austenitization and lower tempering temperature had a stronger impact of DCT on steel properties (hardness, fracture toughness and impact toughness). The observation of DCT effect on hot work tool steels showed that the chemical composition, heat treatment temperature and phase transformation within the material influences the DCT performance.
Speaker Country | Slovenia |
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Register for the Tom Bell Young Author Award (TBYAA)? | Yes |