| Ti-alloys have daily life due to their excellent properties. However, the relatively lowhardness and wear resistance have limited the further applications on certain parts for machine.CBN possesses extremely high strength and hardness. And the present project focuses on theinvestigation of the CBN film by laser cladding in order to improve the hardness of Ti-alloys.The present project involves finite element analysis for the temperature distributionsimulation, the temperature distribution analysis for single pass laser cladding as well asmultiple pass laser cladding, experimental analysis and investigation on the features of themolten pool.First of all, the model of the temperature distribution will be set up based on the finiteelement method, as well as the boundary conditions for heat transfer and the heat source. Andthe parameters of the material’s thermal properties have been determined. Parametricprogramming has been tried with the help of simulation software. In the research ontemperature distribution of the single pass laser cladding, the feature of the temperaturevariation has been investigated during the process of laser cladding. And it was revealed thatthe temperature will be evaluated and lowered very fast in laser cladding. And the parameterselected have been proven to be effective verified by the temperature variation curve of asingle point and the temperature variation curve along certain path. According to theobservation on the influence of various parameters on the temperature distribution, the mosteffective parameters have been found which have been used in the temperature distributionsimulation for the multiple pass laser cladding. The variation of the molten pool at differenttime and passes has been studied in the temperature distribution simulation for the multiplepass laser cladding. And the path together with the law which the cladding process followshas also been determined. The impact of the end effect has been discussed. The temperaturegratitude will reach the maximum value at the interface between the CBN film and the TC11substrate, based on the investigation on the variation of the temperature gratitude alongcertain path, and cracks, air bubbles, and defects are usually present at this region.The formation and features of the molten pool has been studied as well in the current project, andthe impact of different parameters on the geometry features of the molten pool has beenobserved. The research on the characteristic of the diluting rate has also been involved, whichis of great help for improving the quality of the cladding. |
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