稀土、氮对高硼铁基合金凝固组织和性能的影响

Effect of Rare Earth and Nitrogen on Solidification Structure and Properties of High Boron Ferroalloy

研究了稀土、氮复合变质处理对含0.26wt%C,2.05wt%B和0.64wt%Ti的高硼低碳铁基合金凝固组织和性能的影响。结果表明,高硼低碳铁基合金的凝固组织中除了有网状分布的Fe2B化合物外,还存在少量TiB2块状组织;经稀土、氮复合变质处理后,组织明显细化且分布均匀性增加,硼化物中出现了多处明显颈缩和断网现象,没有新相出现,其硼化物仍是Fe2B和TiB2;此外,变质处理对高硼低碳铁基合金硬度无明显影响,但明显提高抗弯强度和冲击韧度。最后分析了高硼低碳铁基合金凝固组织和性能变化的原因。

The influence of rare earth and nitrogen on the solidification microstructure and properties of high boron and low carbon ferroalloy containing 0.26%wtC-2.05wt%B-0.64wt%Ti was researched.The results show that the solidification structures of high boron and low carbon ferroalloy contain Fe2B and TiB2.The shape of Fe2B is network and the shape of TiB2 is block.The amount of TiB2 is obviously less than that of Fe2B.The structures are refined obviously and the distribution of structures is uniform after modified with rare earth and nitrogen.There is no new phase in the modified structure and the borides are still Fe2B and TiB2.There are many obvious necking and broken network in the modified boride.Furthermore,the modification has no obvious influence on the hardness of high boron and low carbon ferroalloy,but increases its impact toughness and bending strength obviously.The reason that rare earth and nitrogen changes the shape of boride and properties is discussed at last.