【摘要】 通过优化合金成分设计、合金化、孕育与变质处理 ,开发出了新型铸造热锻模具钢。该钢具有较高的强韧性和高温稳定性 ,其组织为板条马氏体和贝氏体的复合组织 ,板条间连续分布着许多薄膜状残余奥氏体。在回火过程中有细小的碳化物 V3C4 、Mo2 C弥散析出。采用特种砂 V法铸造工艺获得了良好表面精度和尺寸精度的铸造模具。与传统的锻钢模具相比 ,寿命提高了 40 %～ 1 0 0 % ,具有较高的热疲劳抗力 ,加工余量少 ,不用改锻 ,降低了成本 ,经济效益显著 ,应用前景广阔。更多还原

【Abstract】 A new cast hot work die(CHD) steel has been developed, through optimization of alloy composition design, alloying, inoculation and modification. Results show that CHD steel possesses good strength and toughness and high temperature stability. The microstructures are combined with lath martensite with high density dislocations, bainite, and retained austenite films which distributed at the lathed boundaries continuously. The fine carbides such as V 3C 4 and Mo 2C were precipitated dispersedly during tempering. The fine surface quality and dimensional accuracy cast hot work die was obtained by special sand V method casting technique. Compared with that of conventional forged steel, the life time of the die made of the new cast steel was increased by a factor of 40%-100%. This die has the following advantages: higher resistance to thermal fatigue, fewer machining allowance, no needing forging, higher economic benefit and wider application prospects.更多还原