The Basic Research On Rapid Deposition Manufacturing Based On The Robot

Remanufacturing is a high quality, efficient, less polluting, low-cost green technology,which is a new technology to achieve sustainable development in the21st century. MachineryRemanufacturing is an important branch of remanufacturing, depending on which the damageor destruction of the mechanical parts can restore performance or exceed the performance ofnew products. Common processes for remanufacturing such as thermal spraying, brushplating adhesion and deposition. The deposition forming technology is capable of achieving ametallurgical bond between the materials, and can manufacture high density and excellentmechanical properties parts. The deposition forming has been a key technology for large-scaleequipment such as Mining Machinery, Petroleum Machinery, Turbine, etc. The arc, laser andplasma arc are the common deposition heat source. Plasma arc deposition is less efficient, andlaser deposition costs higher. So this thesis establishes rapid remanufacturing formingexperimental platform based on Six degrees of freedom arc welding robot.Rapid prototyping system based on Arc welding robot has been established. Bydeveloping the Panasonic welding robot software DTPS, the path data can be converteddirectly to the CNC file that the robot can identify, and realize the automation of formingprocess. Circulating water cooling system and rigid constraint control module is designed, andit shows that the two measures can effectively control the deformation of parts through theexperiments. Temperature measurement system is established to measure the temperaturefield of the forming process real-time, in order to study of deposition forming ofthermodynamics.The mathematical model between forming trajectory and the deposition forming processparameters is established by orthogonal experiment design. The problems caused by improperparameters Settings are solved, such as sputter, weld porosity and the uneven shape. It canimprove the tail "shrinkage" phenomenon of vertical deposition through extinction of arcduration and reciprocating deposition method. The problem that geometrical shape is superposition and increase at the small corner can be solved by slowing down and applyingsmall current at the corner. The overlapping of two adjacent horizontal stacking processmodel and height variation in vertical stacking are researched. Finally, the tensile andmetallographic experiments of three-dimensional parts are conducted. The results show thatthe mechanical properties of the formed parts and the filler metal wire material are in littledifference, and there exists remelting phenomenon between two adjacent weld bead.The forming process is simulated by FEA method. The deposition process is simulated byelement birth and death method. The simulation results are in accordance with theexperimental results. The temperature field evolution variation of single-bead and monolayer,single-bead and multi-layer, multi-bead and monolayer deposition is researched. The weldbeads experience preheat before deposition and heat treatment after deposition, except thefirst weld bead which only experience heat treatment after welding, and there exists remeltingphenomenon between two adjacent weld bead. Numerical simulation analysis draws that thedeformation of parts can reduced by optimizing the direction of the deposition and theresidence time between two adjacent weld bead and other measures.