Study On The Preparation And Radiation Damage Behavior Of Plasma Facing Tungsten Coatings

Tungsten is considered to be the most promising plasma-oriented material because of its good thermal conductivity,high melting point,low sputtering rate and low hydrogen isotope absorbability.However,tungsten is difficult to manufacture because of its hardness and brittleness,especially some complex components.Therefore,it is hoped that tungsten coating can be used as plasma-oriented material on the surface of structural materials.Therefore,this thesis prepared tungsten coating on the surface of low activated steel by magnetron sputtering as plasma-oriented material,and studied the effects of magnetron sputtering process parameters,the addition of intermediate layer and the addition of alloying element Ti on the on the microstructure and radiation damage behavior of tungsten coating were studied.(1)Magnetron sputtering coating microstructure structure is significantly influenced by the process parameters and the binding force of matrix,and,in turn,affects the radiation resistance of coating Tungsten coating are mainly BCC tungsten and A-15 w phase,and the preparation of tungsten coating under low pressure than high pressure for the preparation of tungsten coating surface is more compact,and the substrate,the better Among them,the parameters under pressure 2.5 Pa sputtering time60 min tungsten coating preparation for single-phase BCC phase,tungsten coating density,thickness of about four mu m irradiated surface damage degree is low,does not appear obvious nano-fuzz structure,showing good irradiation resistance.(2)In addition,compared with rolled tungsten,the tungsten coating has better resistance to helium ion irradiation.However,with the increase of radiation dose,the surface of the tungsten coating also begins to show obvious damage structure.(3)Compared with the pure W coating,the W-10 Ti coating prepared by adding alloying element Ti has a denser surface and a better bonding force with the substrate,and the added Ti with a mass fraction of 10% is basically solid dissolved in the tungsten substrate.In addition,compared with pure W coating,W-10 Ti coating showed better anti-helium ion irradiation ability under the same helium ion irradiation condition.However,with the increase of radiation dose and temperature,the surface of W-10 Ti coating began to appear obvious nano-fuzz structure.