模具超硬刀具材料高硼化钨的结构研究

Study on the Structure of Tungsten High-Boride as Die&Mold Superhard Tool Material

为研究模具超硬刀具材料高硼化钨的结构,基于WB3-hP16结构,以及调整钨、硼原子对Wyckoff 2b和2c位置的占据成分,建立可能存在的结构体系,运用第一性原理计算,得出高硼化钨的稳定结构应为WB3.86,其中三角硼群的占据1/4的Wyckoff 2b位置,并且计算分析其力学性质,其具有最高的硬度值(42.24GPa),并且其硬度、体变模量、剪切模量和杨氏模量都与其实验更为接近。另外还研究了其微观特性,其费米能位于其最低点,得出结论:高硼化钨的结构为WB3.86结构,为实际合成高硼化钨提供理论依据以及合成配比,更有利于超硬刀具材料高硼化钨的有效合成。

In order to study the structure of tungsten high-boride as a superhard tool material for die&mold,this article is based on the WB3-hP16 structure and adjusts the composition of tungsten and boron atoms occupying Wyckoff 2b and 2c positions,establishing a possible structural system.Using first principles calculations,the stable structure of high boronized tungsten should be WB3.86,with the triangular boron group occupying 1/4 of Wyckoff 2b positions.And through calculation and analysis of its mechanical properties,it has the highest hardness value(42.24 GPa),and its hardness,bulk modulus,shear modulus,and Young's modulus are closer to their experimental values.In addition,its microscopic characteristics were also studied,and its Fermi energy was located at its lowest point,which led us to conclude that the structure of high boron tungsten is WB3.86.Provide theoretical basis and synthesis ratio for the actual synthesis of tungsten high-boride,which is more conducive to the effective synthesis of superhard tool material high boron tungsten.