| With the deep research and application of radiation source, which became important in many fields, such as agriculture, industry and medicine, while the harmfulness to human from it is prominent, for example, the emerging of many diseases induced by it and the threat to the generation of human conducted by a long period of Irradiation. Besides, it may contaminate environment. Radioprotection is essential for those irradiated for a long time, as Electronic equipment and Precision Equipment will be damaged and of electromagnetic interference, which result in Mechanical failure and invalidation. Under the cardinal principle of radioprotection, shielding protection is the most efficient and widely covered one. At present, the screening material applicated mainly consists of stainless-steel with boron, leaded alloy, anti-radiation glass and concretion of lead and boron which is overweight and uneasy to move. improving the boron content of containing boron stainless steel alloy ductility and shock resistance also have adverse effects. lead alloy and with the lead anti- radiation glass also exist secondary ductile induced by radiation, low hardness, poor structure strength can not resist high temperature and, poisonous and other shortcomings.Contained high atomic number, Tungsten’s WC particle enhanced aluminum based composite materials with high atomic number, the gamma ray and neutron shielding performance than lead more excellent, and high stability, high specific rigidity, high specific strength, excellent plasticity, is harmless to the environment is a new structural and functional integration of metal matrix composite radiation protection materials. But in the preparation of this kind of material whether by stirring casting method, reaction formation method and powder metallurgy method, were unable to avoid the mixing process, high density and hardness of WC reinforced in the aluminum matrix settlement and segregation, causing enhanced body evenly distributed, and the impact on the mechanical properties of a material and corrosion resistance.To solve this problem, the studys show that through continuous optimization of mechanical mixing process parameters to improve the mixing uniformity, but the applicability of the method is limited, still unable to effectively solve the problems of settlement of WC grains with high density. This paper in diamond tools, nuclear fuel elements of preparation field mixed feeding stage, the coating method to the WC particles pretreatment, and 2024 Al for mixing, of preparation of WC reinforced aluminum matrix composite compact and uniform distribution and forming excellent. On this basis, this paper also designed the WC reinforced aluminum matrix composites homogeneous distribution of quantitative evaluation method, of pressed blank microstructure image processing using Photoshop and Imagepro software were used with standard deviation S and segregation degree of ζ uniform evaluation index, can be scientific and accurate quantitative evaluation of uniformity after calculation. Finally, preliminary of the preparation of the green compacts were sintered in vacuum, analyzed and discussed before and after sintering pressure blank phase structure, mechanical properties, for the latter part of preparing high performance, high uniformity of WCp/2024 Al composite shielding material can provide theoretical support and technical guidance. The results show that:By using particle coating method for mixing WCp/2024 Al composite powder metallurgy method the deposition and can obviously improve the particle distribution uniformity. by optimizing the coating process parameters, particle percentage to 25 vol.%, mixing speed of 70 r/min, the concentration of the binder to 10 wt.%, the mixing time is 60 min under the conditions of preparing blank particle distribution uniformity is improved obviously.The coating of WCp/2024 Al mixed powders were cold pressed, dense compacts of high density, flat surface, combination of particle and the matrix. WCp/2024 Al composites after sintering, the composite binder removed, but caused by density, hardness and compressive strength were decreased.In a word, the coating mixture of WCp/2024 Al compacts in WC particles uniformly distributed was improved obviously, while the performance needs to be further improved. |
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