The Design And Characterization Of Tailorable Thermal Expansion Structures

Tailorable coefficient of thermal expansion(CTE)structures are coming hot spot due to their shape stability and potential as actuator.However,the studies of the structure,about the design?analysis and verification,are insufficient,especially for the preparation and experiment.In this dissertation,use for reference,the planner tailorable CTE structures which are based on the bi-material beam and bi-material double-arrows are designed,respectively.Meanwhile,two kind of three-dimensional structures that are based on the corresponding planner lattice are designed.Firstly,the planner lattice with modified bi-material beam is designed.Based on the theoretical analysis and numerical calculation,the geometry parameters and materials properties are discussed for their influence to CTE of structure.The result shows that they have obvious effect for the structure expansion.Except that,the dissertation raises one kind of novel preparation process that is based on interlocking.With experimental validity,the structure could get positive or negative by changing the parameter of structure.Then,one kind of two dimensional bi-material arrow structure is designed,similarly,the geometry parameters and materials properties is discussed.Theoretical calculation shows that changing parameters could influence the CTE of structure effectively,and the structure could have anisotropic CTE.Besides,the preparation process with molding is used,and the experiments is processed to valid the feasibility of structure.Finally,the three-dimensional structures are designed though expanding corresponding planner lattice.With theoretical analysis and simulation,the CTE of structure for three directions is deduced and valid.The studies show that the factors that influence the CTE of three dimensional structure is similar to the planner's,and meanwhile,the structures are able to get wide range to tune the CTE from positive to negative.