| Controlled nuclear fusion is considered to be the best way to solve the problem of human energy because of its inherent nuclear security,usable fuel area universality and persistence,and the advantages of environmental protection.Tokamak fusion device is considered to be the most promising way of controlled nuclear fusion and the first wall component of test blanket module faces the plasma directly,which is one of the most key components in the nuclearfusion.Reduced activation ferritic/martensitic(RAFM)steels have been recognized as the primary candidate structural materials for Test Blanket Module(TBM)of fusion reactors because of their inherent features: under the strong irradiation has inherent geometric stability,high heat conductivity,low coefficient of thermal expansion and irradiation swelling and other excellent thermal physical properties,and its reduced activation composition is suitable for commercial production,as well as mature industrial basisi.However,since the first wall directly in the faces the plasma,complex helium cooling channels must be designed to decreasethe thermal acuumulation on the surface,The traditional manufacturing method encounters trick problems,such as complicated process,time material-consuming and thus high cost.The selective laser melting(SLM)additive manufacturing technology is expected to break through the bottleneck of traditional manufacturing method and realize the integrated fabrication of complex structural parts.In this paper,Selecting RAFM(CLF-1)steel as raw material,Spherical powder conforming to SLM forming technology is prepared by argon atomization method,and the CLF-1 steel samples with high dimensional accuracy,high surface quality and nearly complete density are prepared by SLM process parameters optimization.Study the SLM process parameters,including laser power,scanning speed,the laser energy density of the sample surface roughness,the influence of relative density and hardness,Study the influence of SLM laser energy density and different scanning strategy of the forming CLF-1 phase,microstructure and mechanical properties of steel,evaluate its tensile fracture mechanism,in the process of analysis of the tensile fracture morphology,According to the grain structure and its size to estimate the fracture failure mechanism,establish the internal relation between microstructure,mechanical properties,and ]the fracture failure mechanismBased on a kind of nuclear industry independent research and development of south western institute of physics RAFM steel CLF-1 as raw material,adopt the method of argon gas atomization preparation in accordance with the exclusive features RAFM steel spherical metal powder,comprehensive test instrument using laser particle size analyzer,powder etc for arbitrary CLF-1 steel powder characterization test,proved in this paper,the CLF-1 powder liquidity as well as good sphericity and powder particle size in 13 ?m to 57 ?m,is suitable for the SLM technology,The samples with dense structure,high dimensional precision and high surface quality were prepared by using SLM technique through optimizing the process parameters and scanning strategy.Based on the research of SLM two different scanning strategy,by means of two groups of different scanning strategy sample texture intensity,as well as the second phase distribution of grain size and structure analysis of the contrast,the more reason for the difference between the mechanical properties due to the grain size and structure of different under different scanning strategy,its yield strength increase is mainly due to grain refinement,the improvement of toughness is related to its grain structure is different,at the same time reveals the two kinds of sample in the force deformation under different scanning strategy exists the intergranular and transgranular fracture behavior of two different... |
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