析出强化对于Ti微合金钢的强韧化具有重要贡献。针对不同轧制水冷速度下的Ti微合金钢，在明确其显微结构的基础上，采用非水溶液无损电解提取技术获得Ti微合金钢中的纳米碳化物，并根据纳米碳化物的物相组成和粒度分布特征计算出析出强化增量。研究结果表明：Ti微合金钢中存在大量纳米尺寸的M3C和MC类析出物，但较快的水冷速度抑制了二者的析出行为，使得二者占钢的质量分数逐渐减小；同时，水冷速度的提高可细化M3C类析出物粒度，但MC类析出物粒度与水冷速度无明显关系；整体而言，尽管高水冷速度强化了M3C类析出物强化效果，并相对弱化了MC类析出物强化效果，但仍不可忽视MC类析出物的强化贡献。%Precipitation strengthening has an important contribution for Ti microalloy steel strength. With regard to Ti microalloyed steel produced by different rolling water cooling rate, the nano-carbide precipitates in Ti microalloyed steel were obtained by nondestructive electrolysis extraction technology, and its effect on steel strengthening were also calculated based on the phase composition and particle size distribution. The results show that a large number of nano-sized M3C and MC precipitate exists in the Ti microalloyed steel. However, the higher water cooling rate weakens the precipitation behavior of both M3C and MC, which induces that their mass fraction in Ti microalloyed steel decreases. In addition, with the increasing water cooling rate, the size of M3C precipitate decreases, while that of MC precipitate has no significant relationship with the water cooling rate. Generally speaking, the high water cooling rate improves M3C precipitation strengthening and weakens MC precipitation strengthening, but the strengthening contribution of MC precipitate still could not be ignored.
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