Study on the Double-Fined Treatment and Superplasticity of GCr15 Die Steels

Abstract:

Heat treatment has a signifieant impact on the performance of the GCr15 die steel. Using scanning electron microscopy, optical microscopy, hardness tester and tensile testing machine analyses the influence of double-fined treatment on microstructure and mechanical properties of GCr15 steels. The results show that the double-fined treatment can make the carbids which haven’t insoluted fine to 320nm and the grains fine to No. 10. The dislocated martensite become more after double-fined treatment; at the same time, there are more sheet-retained austernite in lathy martensite and around sheet martensite; broken-orifice changes from definitely cleavage brittleness fracture to definitely cleavage tenacity fracture. By double-fined treatment, die steel can be given the neeessary strength and toughness, and the life can be substantially increased. The superplasticity of GCr15 die steel was improved by double-fined treatment. The optimal temperature range of the elongation is: 680~780°C. Anti-oxidants can improve the elongation of GCr15 steels.

• Periodical: Advanced Materials Research (Volume 662)
• Pages: 356-361
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.662.356
• Online since: February 2013
• Authors: Xing Hai Liu, Feng Juan Wu, Hui Bin Wu, Ji Quan Sun, Xue Ping Ren
• Keywords: Double-Fined Treatment, GCr15 Die Steel, Superplasticity

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