Preparation And Performance Study Of Surface Strengthening Coating Of Tungsten Alloy

Tungsten alloys have been widely used in important fields such as military industry and national defense due to their high hardness,high melting point,low coefficient of thermal expansion and other advantages.In recent years,tungsten alloys have become the preferred material for preparing armour piercing projectiles.However,with the continuous development of cutting-edge science and technology,the service environment has become more severe.Therefore,research on improving the mechanical properties of tungsten alloys is of great significance.This article focuses on the 97 W alloy material,using laser surface alloying technology to prepare F65,F65 composite,and GH4169 coatings on the surface of W alloy.Using experimental instruments such as scanning electron microscopy and split Hopkinson pressure bar,relevant mechanical properties are studied from macro micro and dynamic compression aspects,and the dynamic mechanical properties of coated and uncoated tungsten alloys are compared and analyzed.Firstly,this article prepares F65 coating and F65 composite coating on the surface of tungsten alloy,compares and analyzes the experimental results of the substrate and alloying specimens,analyzes the microstructure and phase structure of the two coating materials using scanning electron microscopy,and analyzes the hardness strengthening mechanism of coated tungsten alloy.Secondly,GH4169 coating was prepared on the surface of tungsten alloy,and the macro and micro morphology of GH4169 coating was observed.The phase and element content and distribution in the coating were thoroughly studied.Through high-temperature oxidation experiments,the oxidation kinetics curves of GH4169 coating and W matrix were drawn,and the oxidation products and micro morphology of the oxidized specimens were analyzed.Then,dynamic mechanical tests were conducted on tungsten alloys with F65 composite coating,GH4169 coating,and uncoated coating,and the stress-strain laws were analyzed in depth.Comparative analysis of surface microstructure of tungsten alloy with coating was conducted.Using the stress-strain curves of coated and uncoated tungsten alloys,the constitutive equation was fitted,and the simplified J-C curve was in good agreement with the experiment.Finally,the aforementioned research results were applied to the warhead strengthening of tungsten alloy armor piercing projectiles.Based on the structural characteristics and failure forms of the warhead,a warhead strengthening plan was developed,and the alloying equipment,powder thermal spraying process,key design points of tooling fixtures,and optimal process parameters were elaborated.The preparation of laser alloying coating samples for tungsten alloy armor piercing projectiles was completed,and the prepared samples met the dimensional accuracy requirements.