• 제목/요약/키워드: c-Jun

검색결과 9,002건 처리시간 0.059초

냉간금형 인서트(insert)용 주강의 미세조직 (Microstructure of Tool Steel Castings for Cold-Work Die Inserts)

  • 강전연;박준영;김호영;김병환
    • 열처리공학회지
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    • 제30권5호
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    • pp.197-206
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    • 2017

  • The microstructure of a high-carbon and high-chromium cast steel (HK700) for cold-work die inserts was analyzed by advanced scanning electron microscopy. A continuous network of primary $M_7C_3$ carbide was developed among austenitic matrix after casting. A small amount of $M_2C$ was added to the carbide network owing to the enrichment of Mo and W during the solidification. After quenching in which the austenitization was performed at $1030^{\circ}C$ and double tempering at $520^{\circ}C$, the network structure of $M_7C_3$ was preserved while most of the matrix was transformed to martensite because of additional carbide precipitation. The $M_2C$ in the as-cast microstructure was also transformed to $M_6C$ due to its instability. The continuous network of coarse carbides owing to the absence of hot-working had little influence on the hardness after quenching and tempering, whereas it resulted in severe brittleness upon flexural loading.

  • https://doi.org/10.12656/jksht.2017.30.5.197 인용 PDF KSCI