Study On Semi-solid Pressure Bonding Of Steel-Ti Composite Plate

As a new type of composite material,steel-titanium composite board has excellent comprehensive performance and can meet the requirements of component materials such as aircraft skin.In order to solve the problems of the complicated production process,high processing material cost and poor composite interface performance in the preparation method of metal composite board,a semi-solid pressure bonding method is proposed in this paper.By reasonably controlling the bonding process parameters,steel-titanium composite plates with good interface properties are prepared.The main research contents and achievements are as follows:1.The titanium alloy semi-solid slurry containing 3%by mass of Ni was successfully prepared by using electromagnetic stirring method.The primary solid phase morphology is spherical or nearly spherical which can meet the experimental requirements.The relationship between the solid phase ratio and the stirring temperature of the semi-solid slurry is obtained by rapid cold quenching experiments.2.Using finite element simulation software ABAQUS to simulate the residual stress generated on the interface during the semi-solid pressure bonding process of steel-titanium composite plate.The process parameters when the interface residual stress is small are obtained.A better process parameters are initially determined to provide guidance for subsequent pressure bonding experiments:the indenter load is 65 MPa,the preheating temperature is 550? and the pouring temperature of 1505?.3.The steel-titanium composite plates with good interface bonding performance are successfully prepared by semi-solid pressure bonding experiment:(1)The relationship between the indenter load,the preheating temperature,the pouring temperature and the shear strength of the composite interface of the steel-titanium composite plate is obtained by the shearing experiment.With the increasing of the indenter load,preheating temperature and pouring temperature,the interfacial shear strength increases first and then decreases.(2)The process parameters with the best interface bonding performance are obtained by orthogonal experiment:the indenter load is 65 MPa,the preheating temperature is 550 0C and the casting temperature is 1505 0C.The influence degree of each process parameter on the interface shear strength is pouring temperature>preheating temperature>indenter load.(3)Conduct research on the microstructure of the composite interface.The forming mechanism of different composite interface under different process parameters is discussed.It is clarified that the composite interface under the optimal composite process parameters is an alternating structure of iron-titanium compound and iron-titanium solid solution.The compound on the composite interface is measured as FeTi.