TiZr基非晶合金熔体与TiZrCu合金的润湿行为与界面特征

发布时间：2018-06-20 07:42

本文选题：非晶 + 润湿性　；参考：《沈阳理工大学》2017年硕士论文

【摘要】：近年来,Ti基非晶合金的非晶形成能力成功提高到了厘米级,Ti基块体非晶也因其高强度、低密度等特性在工程结构材料中有良好的应用前景。但是,室温下块体非晶极低的塑性却限制了它的应用。通过引入增塑相,制备非晶复合材料可以有效改善块体非晶的塑性。最近,对于非晶复合材料的结构可控制备逐渐受到了科研人员的关注,这对开发具有高性能的非晶复合材料具有重要意义。外加法是一种简单并且可控性强的制备复合材料的方法,而内生型非晶复合材料中的两相具有十分优异的相容性和界面结合质量。本文从基体与第二相的润湿性与固液交互作用出发,研究了层状复合Ti32.8Zr30.2Ni5.3Cu9Be22.7非晶和与之具有良好相容性的Ti_(61.5)Zr_(36.4)Cu_(2.1)合金的可行性和复合后材料的微观结构组成。研究了Ti32.8Zr30.2Ni5.3Cu9Be22.7非晶与Ti_(61.5)Zr_(36.4)Cu_(2.1)合金的润湿行为,二者具有良好的润湿性。连续升温过程中润湿角分两次减小,在750、800和850℃保温时,润湿动力学曲线分为快速减小阶段和稳态阶段。界面上发生Ti_(61.5)Zr_(36.4)Cu_(2.1)合金的溶解反应,固液交界处形成了结合质量很好的原子扩散层。非晶合金熔化后,内部析出了初级晶化产物,800℃时该产物完全消失。因此,制备复合材料时需将温度控制在800℃以上用水淬法制备了液桥样品来模拟层状非晶复合材料的结合,研究了层状非晶复合材料的结构。结果表明,在800℃以上制备的复合材料是由部分Ti_(61.5)Zr_(36.4)Cu_(2.1)合金溶解进入非晶层中形成的非晶复合材料层与剩余Ti_(61.5)Zr_(36.4)Cu_(2.1)合金层组成的。基于Ti32.8Zr30.2Ni5.3Cu9Be22.7与Ti_(61.5)Zr_(36.4)Cu_(2.1)间良好化学成分稳定性,非晶复合材料层由Ti32.8Zr30.2Ni5.3Cu9Be22.7非晶基体与β-Ti(Zr,Cu)枝晶相组成。一定冷速条件下,Ti32.8Zr30.2Ni5.3Cu9Be22.7熔体对Ti_(61.5)Zr_(36.4)Cu_(2.1)有一定的溶解度,非晶熔体中Ti_(61.5)Zr_(36.4)Cu_(2.1)的浓度需超过溶解度才能在凝固过程中析出枝晶相。随保温时间延长,基片溶解反应逐渐停止,复合材料层中的枝晶相分布逐渐均匀。统计液桥样品基片的溶解深度,由于Ti_(61.5)Zr_(36.4)Cu_(2.1)的密度略小于Ti32.8Zr30.2Ni5.3Cu9Be22.7熔体的密度,液桥样品下基片受到了重力驱动对流的作用,所以其溶解深度略大于上基片。选择了一种溶解深度预测模型对基片溶解深度进行拟合,并且验证了拟合数值的正确性。根据该模型的拟合值可以了解不同温度下复合材料层中均匀分布的枝晶相的体积分数,从而控制复合材料层的性能。另外,还可以利用该模型设计层状材料层间厚度比,达到控制层状复合材料整体性能的目的。
[Abstract]:In recent years, the amorphous formation ability of Ti based amorphous alloys has been successfully raised to centimeter level. The amorphous Ti based bulk has a good application prospect in engineering structure materials because of its high strength and low density. However, the low amorphous plasticity at room temperature limits its application. By introducing plasticized phase, the preparation of amorphous composites can be made. The plasticity of the bulk amorphous is effectively improved. Recently, the control of the structure of amorphous composites has gradually attracted the attention of the researchers, which is of great significance for the development of high performance Amorphous Composites. In this paper, the feasibility of the laminated composite Ti32.8Zr30.2Ni5.3Cu9Be22.7 amorphous and Ti_ (61.5) Zr_ (36.4) Cu_ (2.1) and the microstructure of the composite after the wettability and solid liquid interaction of the matrix and the second phase are studied. The wetting behavior of Ti32.8Zr30.2Ni5.3Cu9Be22.7 amorphous and Ti_ (61.5) Zr_ (36.4) Cu_ (2.1) alloy was investigated, and the two had good wettability. The wetting angle was reduced two times during the continuous heating process. The wetting kinetics curve was divided into a rapid decrease stage and a steady state at 750800 and 850 C. Ti_ (61.5) Zr_ (36.4) Cu_ (2.1) occurred on the interface. The dissolving reaction of the alloy formed a good atomic diffusion layer with good quality at the junction of solid and liquid. After the melting of the amorphous alloy, the primary crystallization product was precipitated, and the product completely disappeared at 800 C. Therefore, the temperature of the composite material was controlled at 800 degrees centigrade, and the liquid bridge sample was prepared by water quenching to simulate the layered amorphous composite. The structure of layered Amorphous Composites is studied. The results show that the composite material prepared at above 800 degrees C is composed of amorphous composite layer formed in the amorphous layer by partial Ti_ (61.5) Zr_ (36.4) Cu_ (2.1) alloy and remaining Ti_ (61.5) Zr_ (36.4) Cu_ (2.1) alloy layer. Based on Ti32.8Zr30.2Ni5.3Cu9Be22.7 and Ti_ (61.5) Z) The stability of chemical composition between r_ (36.4) Cu_ (2.1), amorphous composite layer composed of Ti32.8Zr30.2Ni5.3Cu9Be22.7 amorphous matrix and beta -Ti (Zr, Cu) dendrite. Under certain cold speed conditions, Ti32.8Zr30.2Ni5.3Cu9Be22.7 melts have certain solubility to Ti_ (61.5) Zr_ (36.4) Cu_ (2.1), Ti_ (61.5) Zr_ (2.1) in amorphous melt. The dendrite phase can be precipitated during the solidification process. With the prolongation of the heat preservation time, the dissolution reaction of substrate dissolves gradually and the dendrite phase distribution in the composite layer is evenly distributed. The dissolution depth of the base sheet of the liquid bridge sample is statistically less than the density of Ti_ (61.5) Zr_ (36.4) Cu_ (2.1) less than the density of the melt in the liquid bridge, and the liquid bridge sample The substrate is driven by the action of gravity driven convection, so the dissolution depth is slightly larger than that of the upper substrate. A solution depth prediction model is selected to fit the dissolution depth of the substrate, and the correctness of the fitting value is verified. The volume fraction is used to control the properties of the composite layer. In addition, the model can be used to design the thickness ratio between layers of layered materials to control the overall performance of layered composites.
【学位授予单位】：沈阳理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TG139.8

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