Study On Al-Al₂O₃ Laminated Structure Prepared By Thermal Spray Technology

In recent years,"additive manufacturing technology" caused a great attention at both home and abroad,many researchers have a great interest in the new manufacturing technology.At the same time,many experts think that this technology will give rise to a new generation of industrial revolution.Additive manufacturing technology is also known as 3D print technology;it is a kind of new manufacturing technology that through material accumulation layer by layer,gradually develops from 2D to 3D.Military aviation,health care and electronic science and technology material preparation is its main application direction.Beijing institute of aviation manufacturing engineering professor Guanqiao introduced the concept of "generalized additive manufacturing".generalized additive manufacturing technology not only refers to the layered deposition forming,also include a lot of traditional method forming technology such as physical(chemical)vapor deposition,welding(compound)forming,spraying forming and so on.Multilayer composite materials,also known as sandwich material,have great market value because of its advantages of component materials.Till to now,additive manufacturing technology for the preparation of complex shape of multilayer structure material is still difficult.In this topic,using thermal spraying technique(high velocity arc spray and Oxygen--acetylene flame spray)as the main technical method,combined with rapid prototyping technology,in electric arc spraying Al coatings and flame spraying aluminum coatings,fabricate metal-ceramic-metal layered composite structure material.Finally test the material heat insulation performance we made,the test result shows that the layered structure of the coefficient of thermal conductivity is less than 30% of aluminum materials made by tradition method,heat insulation effect is obvious.At the end,preparation a layered structure composite goblet entities by thermal spray forming technology.The outstanding problems of the thermal spraying additive manufacturing technology for preparation multilayer structure is easy to appear coating crack,damage,or even fall off under the condition of working.At the same time,we still studied the mechanical properties of the multilayer structure;To evaluate the mechanical behavior of carbon steel/aluminum double-layer structure,using the theory of bending beam and the technology of nano indentation test the elasticity modulus of the multilayer structure,the data can reflect the multilayer structure mechanical properties in the process of service.By optical microscope,field emission scanning electron microscope to observe the surface morphology and fracture morphology before and after the bending test,the failure mechanism of multilayer structure has been studied.Testing results explain the failure mode of the coating,simulation the multilayer structure failure process under the condition of three point bending by the finite element software Abaqus 6.12,compared with the real test results,test results demonstration that the actual load-displacement curve are in accord with finite element software simulation,proved the accuracy of the experiment.