微量碳掺杂化学气相沉积钨的制备及其表征

Preparation and Characterization of Micro-carbon Doped Chemical Vapor Deposition of Tungsten

未来聚变装置的稳态运行对面向等离子体材料性能提出了更高的要求。为细化CVD-W材料柱状晶尺寸,以提高CVD-W材料的室温力学性能和高温结构稳定性,研究采用在CVD-W材料中掺杂微量碳元素以提升材料性能、细化微观组织的方法。该方法采用裂解器700℃活化后的甲烷作为气态C源,与六氟化钨(WF6)、氢气(H2)共同作为原材料,在温度为550℃的铜基材表面发生化学气相沉积反应制得微量C掺杂(Trace amount of Carbon-Doped,TCD)CVD-W涂层。研究发现:当TCD-CVD-W涂层中掺杂的C含量为0.0156%时(质量分数),涂层纵剖面的显微硬度从377 HV1.0上升至825 HV1.0,晶粒尺寸得到显著细化;X射线衍射(XRD)发现该TCD-CVD-W涂层中存在碳化二钨(W2C)物相。

Theoperation of fusion devices in the future requires higher performance of plasma-oriented materials.In order to refine the columnar crystal size of CVD-W materials and improve the mechanical properties at room temperature and structural stability at high temperature,the papertries to dope trace carbon elements in CVD-W materials to improve material performance and refine the micro-structure.Methane activated by a cracker at 700℃is used as a gaseous C source,and tungsten hexafluoride(WF6)and hydrogen(H2)are used as raw materials.A Trace amount of Carbon-Doped(TCD)CVD-W coating is prepared by chemical vapor deposition reaction on the surface of copper substrate at 550℃.It is found that when the content of C doped in TCD-CVD-W coating is 0.0156%(mass fraction,the same below),the micro-hardness of the longitudinal section of the coating increases from 377 HV1.0 to 825 HV1.0,and the grain size is significantly refined.X-ray diffraction(XRD)shows that tungsten carbide(W2C)phase exists in the TCD-CVD-W coating.