The microstructure and the stability of carbides after heat treatments in an H23 tool steel were investigated. The heat treatments consisted of austenization at two different austenizing temperatures (1100\u00b0C and 1250\u00b0C), followed by water quenching and double-aging at 650\u00b0C, 750\u00b0C, and 800\u00b0C with air cooling between the first and second aging treatments. Martensite did not form in the as-quenched microstructures, which consisted of a ferrite matrix, M6C, M7C3, and MC carbides. The double-aged microstructures consisted of a ferrite matrix and MC, M6C, M7C3, and M23C6carbides. Secondary hardening as a consequence of secondary precipitation of fine M2C carbides did not occur. There was disagreement between the experimental microstructure and the results of thermodynamic calculations. The highest double-aged hardness of the H23 tool steel was 448 HV after austenization at 1250\u00b0C and double-aging at 650\u00b0C, which suggested that this tool steel should be used at temperatures below 650\u00b0C.<\/p>\n
Dibuat oleh :\u00a0Meilinda Nurbanasari,\u00a0Panos Tsakiropoulos,\u00a0Eric J. Palmiere<\/p>\n
E-mail:\u00a0 meilinda@itenas.ac.id<\/p>\n
Kata Kunci : \u00a0tool steel, microstructural evolution, heat treatment, carbides, stability, hardness<\/p>\n
Keterangan : \u00a0Makalah ini\u00a0 dimuat pada International Journal of Minerals, Materials and Metallurgy, Vol. 22, No. 3, page 272-284.<\/p>\n
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