Fabrication And Properties Of Neutron-resistant ?-Ray Absorbing Shielding Material W-Al-B₄C

B₄C materials have good absorption of neutrons,and have the advantages of low density,high strength,stable chemical properties,and low thermal swelling rate.They are currently widely used in neutron shielding materials;Al metal materials have better toughness.And low density,as the matrix of the composite material can improve the tensile strength and wettability of the material;the addition of W material can improve the hardness and high temperature and corrosion resistance of the composite material,while tungsten is a material that shields?rays;W-The Al-B₄C composite material takes into account the toughness and low density of Al,and at the same time has the high hardness of B₄C and W materials.The W-Al-B₄C composite material can comprehensively shield neutrons and gamma rays.It provides a very important reference value for the research of new comprehensive shielding materials.In this thesis,W-Al-B₄C composite materials were prepared by vacuum sintering.The main research results are the following three points:First:The Monte Carlo method and MCNP5.0 software were used to simulate the neutron and?-ray shielding properties of the W-Al-B₄C composite material.The main parameters affect the neutron and?-ray transmittance.The study found that when the B₄C content of the material is 35%and the thickness is 3cm,the composite material has a good shielding effect on 0.1Mev neutrons;when the W content of the material is 25%and the thickness is 3cm,the composite material is 0.1Mev photon the shielding effect is better.Second:Five composite materials with different ratios of5W-60Al-35B₄C,10W-60Al-30B₄C,15W-60Al-25B₄C,20W-60Al-20B₄C,and 25W-60Al-15B₄C were prepared by powder metallurgy Material thermal expansion,linear expansion,TG-DSC,micro-morphology,EDS,physical properties,phase composition were analyzed.The study found that when the temperature is 500?-600?,the thermal expansion coefficient and linear expansion coefficient of the material rise faster;the composite material produces an endothermic peak at 100?,and the thermal weight of the material is the lowest value at 300?;the particles of the composite material The combination is good,the distribution is uniform,and no other components are produced;the density of the material is light,the hardness meets the needs of general structural materials,and the material does not produce new phases.Third:The effects of preparation technology?pressing pressure,sintering time,sintering temperature,and heating rate?on the microstructure,density,density,hardness,phase and shielding properties of W-Al-B₄C composites were explored.The study found that the W-Al-B₄C composites prepared with a pressing pressure of 200 MPa,a sintering temperature of 600°C,a sintering time of 60 min,and a heating rate of 10°C/min have high density,compactness,and high hardness,with uniform particle distribution and pore Relatively reduced,the particles are tightly bound,and the shielding performance of the material is better.