The microstructure and tensile properties of W/Ti multilayer composites prepared by spark plasma sintering

In order to improve the toughness of W, a series of W/Ti multilayer composites are prepared by spark plasma sintering ranging from 1000 degrees C to 1400 degrees C. The relation between the microstructure and the properties is systematically investigated. The W/Ti multilayer laminates have a better comprehensive property when the sintering temperature is between 1000 degrees C and 1200 degrees C. Under those conditions, the elongated grains in the W layers are maintained. Meanwhile, the interface microstructure of the laminates can be divided into three layers, including beta-W(Ti) solid solution with lamellas, beta-Ti(W) solid solution and nanosized martensite with a beta-matrix and alpha phase in basketweave microstructure. The orientation relationship between the alpha-Ti variants and the beta-Ti matrix is determined to be the Burgers orientation relationship. The intervariants boundaries between different alpha colonies are 60 degrees/[11 (2) over bar0]. The fracture mechanism of the composites shows a mixed facture mode and debonding of the interfaces. The fracture of the W layers is transgranular cleavage fracture and lamellas fracture, and the fracture of the Ti layers is ductile fracture with dimples. (C) 2018 Elsevier B.V. All rights reserved.

为了提高钨（W）的韧性，通过放电等离子烧结在1000℃至1400℃的温度范围内制备了一系列钨/钛（W/Ti）多层复合材料。系统地研究了微观结构与性能之间的关系。当烧结温度在1000℃至1200℃之间时，钨/钛多层复合材料具有更好的综合性能。在这些条件下，钨层中的拉长晶粒得以保留。同时，复合材料的界面微观结构可分为三层，包括具有片层状的β - W(Ti)固溶体、β - Ti(W)固溶体以及具有β基体和篮状组织α相的纳米马氏体。确定α - Ti变体与β - Ti基体之间的取向关系为伯格斯（Burgers）取向关系。不同α集落之间的变体间边界为60°/[11 (2) 上划线0]。复合材料的断裂机制呈现出混合断裂模式以及界面脱粘。钨层的断裂为穿晶解理断裂和片层状断裂，钛层的断裂为具有韧窝的韧性断裂。（C）2018爱思唯尔有限公司。版权所有。