【作者】 刘志科；

【导师】 苏广才；

【作者基本信息】 广西大学 ， 材料加工工程， 2006， 硕士

【摘要】 与外加法相比，原位合成法因其工艺简单、材料性能优异，在技术和经济上更为可行。增强体原位合成避免了其污染问题，也解决了熔铸过程中存在的两相润湿性问题，有利于制备性能更好的复合材料。在国内外，对于原位合成颗粒增强金属基复合材料的研究主要集中在制备工艺以及机械性能上。鉴于以上原因，本文通过原位法制备了TiCp／Fe和VCp／Fe复合材料，并对其微观组织、增强颗粒生长机制以及界面反应等进行了研究，主要研究成果如下： 1、利用原位合成法在大气环境中制备了TiC或VC颗粒增强铁基复合材料。X衍射分析的结果表明：原位合成的增强体为TiC、VC，并从衍射谱中标出TiC的最强峰(200)，VC的最强峰(111)。 2、增强体在基体中分布均匀，TiC颗粒呈四边性或近似等轴状，VC颗粒为短纤维状。通过对元素分布进行定性分析，知道在增强相中固溶了少量Fe元素，基体中溶有Ti或V元素。在TiCp／Fe复合材料中有少量的黑色相生成，经硬度、能谱以及TEM分析确定该相为石墨相。 3、从动力学、增强相的凝固过程以及晶体结构三个方面对TiCp／Fe复合材料中增强相TiC的生长机制进行了探讨。增大溶质浓度和适当提高反应温度可以提高颗粒长大速度，Tic的形成过程为形核、长大、堆砌和规则化。TiC相按照其Fm3m点群确定的立方六面体晶型成型，该立方六面体由六个(100)面组成。更多还原

【Abstract】 Compared with traditional techniques, in situ technique owe following advantages: it is very simple and material’s properties are excellent, so it is easier to fabricate Fe matrix composites in technology and economic. Ceramic particle of in situ synthesis avoids pollution and wettability existing in casting technique, so it is valuable to fabricate Fe matrix composite with better properties. But at present, more attentions are fastened upon preparation progress and MMCs’ mechanical properties. As the reasons mentioned, TiCp/Fe and VCp/Fe composite have been prepared and their microstructure, reinforcement growth mechanism, interface also have been studied.1 、 Fe matrix composites reinforced with TiC or VC have been produced by in situ technique. The results of X ray diffraction show that the in situ synthesized reinforcements are TiC and VC. We can conform the first strongest peak of TiC is (200) and VC is (111).2、 The reinforcements were distributed uniformly in matrix alloy. The shape of TiC is quadrangle or near-equated shape, and VC has the shape of whisker. Qualitative analysis of element distribution told us that there are a spot of Fe dissolved in reinforcements and a few of Ti or V dissolved in matrix. In TiC/Fe composite, some graphite is created.3 、 TiC reinforcements’ growth mechanism were discussed from kinetics, solification and crystalline structure. Augmenting solute concentration and更多还原