Structrue Design Of Selective Laser Sintering Powder Transmission Device

As a convenient Rapid Prototyping(RP)technique,Selective Laser Sintering has been experimented a series of trials at home and abroad in the past three decades.Owing to the Selective Laser Sintering industry started relatively late in China compared with western developed countries,a large disparity existed undoubtedly.At present,the influence of each parameter on molding quality is only studied in terms of process parameters,and the comprehensive research data is lacking.The structure of the transmission device is simple,the accuracy and stability has a big dismantling compared with the foreign countries.Therefore,this paper mainly studies the influencing factors of molding quality,and improves the molding cylinder and the powder laying system.In this paper,we studied the influence of processing parameters on the quality of sintering molding parts,by cnsidering the processing parameters such as layer thickness,laser power,scanning distance,scanning speed,processing temperature and time intervals between layer and layer,we can get the affective elements that influence the shrinkage deformation,warping curvature,density and tensile strength of molding parts so as to find the influential trend of sintering parts and maximize the capability of it under the optimal processing conditions.To adopt the primary deceleration structure in powder laying transmission system can decrease the need for stepper motors;considering the oversize amount of sintering weight and inside molding cylinder powder in the heating,instead of scheme of directly transmission base plate by ball screw bar,a sleeve is added to the outside ball screw bar which connected the bar to it for holding against the board,so to improve the accuracy and stability of transmission;base palate undirectly linked to bottom and placing a heat insulation board can prevent a large amount of power in sintering processing.In the configuration of powder laying,using synchronous belts to drive of both sides at the same time can ensure the synchronism of that step;one aspect of powder laying board in front ofthe bar not only guarantee the homogeneity but compacted powder.In the procedure of laser simulate the Selective Laser Sintering,dealing with the distribution of temperature field and taking numerical simulation of temperature field under the condition of laser continuous movement in powder,through adjusting the laser power to get distribution of working surface temperature field in different laser rates,consequently,the temperature curve of the cross section can be derived,and the width of the weld can be analyzed under the different laser power.Therefore,we can be provided with theoretical directions and basis for practical tests.In summary,this text including the influence of processing parameters on molding parts,which further more studied how to improve the transmission structures of molding cylinder and powder laying machine.By means of the temperature field spread of simulating laser in the process of continuous movements in sintering surface,which can offer a deeper theoretical and technological support...