【作者】 张志强；

【导师】 姜启川；

【作者基本信息】 吉林大学 ， 材料加工工程， 2006， 硕士

【摘要】 本文主要研究了DTA条件下Fe-Ti-B4C体系反应的路径,探讨了Fe含量、Ti粉粒度和B4C粉粒度对SHS燃烧温度和燃烧合成产物的影响规律,并选择较佳的体系成功地制备了TiC和TiB2颗粒局部增强低Cr钢基复合材料,探讨了预制块中Fe含量的变化对局部增强复合材料微观组织和耐磨性的影响。DTA条件下Fe-Ti-B4C体系反应生成TiC及TiB2的主要路径可能如下:首先是Fe和B4C反应生成Fe2B和C,然后Fe和Ti相互扩散形成FeTi,FeTi和Ti形成共晶液相,Fe2B和C溶解到液相中,与Ti反应生成TiC和TiB2,最后陶瓷颗粒从液相中析出。研究表明,Fe含量、B4C粉粒度对Fe-Ti-B4C体系中SHS反应的燃烧温度和合成产物的微观组织影响较大,Ti粉粒度对其影响较小。低Cr钢基复合材料由三个区组成:(i) TiC和TiB2颗粒增强区;(ii)过渡区和(iii)基体区;在过渡区,仅有TiC颗粒存在而没有TiB2存在;在不同砂纸粒度和不同载荷条件下,Fe含量为30 wt.%的Fe-Ti-B4C-C体系制得的低Cr钢基复合材料局部增强区的耐磨性最好,其次为20 wt.% Fe,钢基体最差,加入TiB2和TiC陶瓷颗粒极大地提高了钢基体的耐磨性。更多还原

【Abstract】 Iron and steel have been extensively used in modern mechanical and metallurgy industry as structure materials. With the development of science and technology, a challenge appears for the conventional iron and steel, because they cannot meet the demands for super mechanical properties. In order to solve this problem, many scientists have intensively studied the steel matrix composites by ex- and in-situ incorporation of ceramic reinforcements into steel matries, which possess combined properties of toughness and machinability related to the conventional steel or iron and high hardness and good wear resistance related to the ceramic.The fabrication methods of particulates reinforced metal matrix composites can be classified into two types: in-situ method and ex-situ method. Compared with the conventional MMCs fabricated by the ex-situ methods, the in-situ MMCs have the following advantages: (i) the reinforcement is thermodynamically stable in the matrix, leading to less degradation at elevated-temperatures; (ii) the interface更多还原