冲击磨损条件下WC/钢基表层复合材料的界面重熔调控及其与性能间的关联机制

Under complex wear condition with impact, the ceramic particles reinforced steel matrix surface composites have be a new research focus in many industries, such as mining, building materials and so on. The life of composites depends on the interface control. This project selected tungsten carbide particles reinforced steel matrix surface composites as the research target, provides an idea named “interface remelting” in which the interfacial phases, their morphology and the interface width would be adjusted by remelting of the interface so as to control the properties of the composites. Firstly, the composites will be fabricated and remelted by a process of multilayer preform sintering + vacuum interface remelting. Secondly, the thermodynamics and dynamics mathematical model for the interface remelting will be set up by combining both theoretical calculation and experiments. Finally, combining the study on blocking effect at the microscopic interface and load response at the macroscopic interface, the connection between the interface remelting control and the impact wear properties will be explored, and the common scientific law, e.g., the connection mechanism between the interface control and the composite properties will be solved. The project could greatly enrich the composite interface control theory, support successful application of the composite under impact wear condition in theory.

在矿山、建材等行业使用的抗冲击磨损耐磨材料中，陶瓷颗粒增强钢基表层复合材料成为新的研究热点，其寿命与界面控制密切相关。项目以碳化钨颗粒增强钢基表层复合材料为研究体系，提出通过界面重熔方法调节界面特征（物相、形态及宽度等），从而控制材料性能的思路。首先采用多层结构的预制坯烧结+真空界面重熔工艺，实现表层复合材料的制备和重熔；然后利用理论计算和实验方法，建立界面重熔热力学和动力学数学模型，揭示界面重熔机制；最后结合微观界面的阻断效应和宏观界面的载荷响应研究，探索界面重熔控制与冲击磨损性能间的关联性，解决陶瓷颗粒增强钢基表层复合材料的界面调控及其与冲击磨损性能间的关联机制等共性科学问题。项目的实施将丰富陶瓷颗粒增强钢基表层复合材料的界面控制理论，并为其在冲击磨损复合工况下的成功应用奠定理论基础。

陶瓷颗粒增强钢基表层复合材料在矿山、建材等行业已获得成功应用，尤其是在抗冲击磨损等复合磨损工况中，如何调控复合材料中陶瓷颗粒与基体间的界面已成为新的研究热点。项目以碳化钨颗粒增强钢基表层复合材料为研究体系，利用界面重熔方法来调节界面特征（物相、形态及宽度等），改善材料的界面反应区，微观宏观界面能有效传递载荷，阻碍裂纹扩展，使复合材料压缩性能得到提高。当重熔温度在1300℃~1340℃，重熔时间在60~100min区间内时，界面形态结构完善，宽度适宜。随着重熔温度的升高和重熔时间的延长，界面反应层中的晶粒逐渐生长。结合微观界面的阻断效应和宏观界面的载荷响应研究，探索界面重熔控制与冲击磨损性能间的关联性，随重熔温度的变化，复合材料在冲击磨损实验120min后的累积磨损量均为先上升后下降，并在重熔温度1280℃-1320℃之间达到累计磨损量的最小值。项目的实施将丰富陶瓷颗粒增强钢基表层复合材料的界面控制理论，并为其在冲击磨损复合工况下的成功应用奠定理论基础。