Reaserch On Flow Properties Of Molten And Control Method Of Sensitivity Parameters On Induction Cladding

Combined with induction heating and surface technology,induction cladding technology is used to obtain alloy coating with wear-and corrosion-resistance.As for the layer,it can be manufactured by form ionic bond with low cost.Viewed as a kind of energy conservation and environment protection technology,induction cladding has the potential application value in industry.Currently,control process of induction cladding limits its wide application.The control process,including a variety of factors,interaction parameters and complex physical parameters,make it difficult to control precisely for the cladding quality.It is urgent to optimize and research during induction cladding.As for the existing problems of control process on induction cladding,the induction cladding parameters with different process condition is analyzed by the methods,which is consist of experimental measurement,numerical simulation and theoretical analysis.With great influence on the quality of cladding,the sensitivity parameter is explored.Based on the methods and strategies of sensitivity parameter,the forming mechanism of induction cladding molten pool is analyzed.Establishing the process planning strategy on optimizing control of sensitivity parameter,it provides theoretical basis and reference data for achieving precise optimizing control in the process of induction cladding.The research works in this paper are mainly based on the following content:(1)Research on the molten pool forming mechanism of induction cladding.Based on the heat-transfer properties of induction cladding,the heat transfer and flow model of molten pool is established.The verified numerical simulation of temperature field is used as the temperature gradient driving source to establish the molten pool model.The influence discipline of loading frequency and current to area and flow velocity of molten pool is revealed.Meanwhile,the influence discipline of molten pool flow to micro-hardness and solute diffusion is clear.The molten pool model shows that the vector movement of molten pool is vortex motion.The flow velocity rises with increasing heating time.Simultaneously,the maximum flow velocity is located in the inside of substrate.In the process of substrate melting,the liquid metal with high flow velocity makes contribution to deepen the molten pool by driving the liquid phase.The convection degree of bonding area can be characterized by the maximum flow velocity of inside molten pool.It reflects the metallurgical bonding strength and hardness directly.What’s more,the degradation degree can be reflected by the maximum flow velocity of outside molten pool.It is the representation of molten pool expansion capability.Loading current is directly proportional to the influence of molten pool forming and flow velocity.However,as for the loading frequency,it is disproportional to that of molten pool.In certain range of loading frequency,the existing extreme value is essential to optimize cladding parameter and improve induction cladding quality.(2)Research on sensitivity parameter during induction cladding.With theoretical analysis of process factor and quality target parameter,Taguchi orthogonal experiment is designed to analyze sensitivity parameter.Based on the numerical model to simulate the induction cladding process with different parameter under the guidance of orthogonal experiment,the quantitative analysis of numerical results to process factor is definite.The key sensitivity parameter factor,which has great influence on three target parameter,including cladding quality,maximum substrate temperature gradient and phase change layer thickness ratio,is defined.Exploring the influence of controllable sensitivity parameters to target parameter,the setting procedure of parameter factor and target parameter is analyzed.Based on range analysis,the optimum combination parameters of sensitivity parameter can be obtained.(3)Research on the optimizing control process of sensitivity parameter during induction cladding.Designing the optimizing experiment of sensitivity parameter,using the method of frequency conversion adjustment and clearance ratio optimization,the induction cladding is studied with the analysis of sensitivity parameter to cladding process.Based on target parameter analysis of finite element modeling and cladding experiment,the control process of sensitivity parameter is optimized.As for improving induction cladding quality,planning and strategy of sensitivity parameter is put forward by exploring the way of frequency optimization adjustment.(4)Analysis of variable frequency induction cladding experiment.Optimizing frequency to adjust parameter and setting the control system,the real-time frequency adjustment is fulfilled on the basis of variable frequency induction cladding platform.Measuring the surface temperature of cladding by infrared sensor,the real-time frequency automatic adjustment meets the demand of sensitivity parameter optimization control.With numerical simulation and cladding experiment,the influence of real-time frequency adjustment to optimization control process is analyzed.According to the research on molten pool forming mechanism,sensitivity parameter analysis and optimizing control of sensitivity parameter,high performance computing of induction cladding numerical simulation is achieved.The design of induction cladding platform can monitor temperature in real time.Based on cold coating optimization,high quality coating is obtained.The variable frequency induction cladding model can be verified by cladding temperature field.The research works provide a reliable numerical model and experiment equipment for exploring forming mechanism of induction cladding and optimizing control of sensitivity parameter.It is of great significance to the research and development of control process during induction cladding.