Research On Selective Laser Sintering Of Polystyrene/Glass Fiber Composites And Molding Process

Taking into consideration of the following characters,such as rather brand processing temperature range,rather better flowing quality and rather better forming accuracy,PS used in SLS is regularly applied in the investment casting field.However,some of them are hardly ever used as the function parts directly because of insufficient intensity of them.In this study,the material preparation of PS/GF powders,SLS prototyping mechanism and optimization of prototyping process were analysed systematically,moreover,some experiments related to this research were carried out to provide more evidence and actual data.The experimental results show that the molding quality of sintered parts was improved,which has great significance in application of the function part made of PS sintering parts.First of all,according to the material properties of PS and GF,selection and surface treatment of materials,the material preparation process and thermal analysis were confirmed.The forming mechanism of PS/GF powders based on the SLS were comprehensively analysed in term of the working principle of the SLS,heat transfer process of the laser and sintering mechanism.Secondly,the systemic analysis was studied to confirm the SLS process parameters.The rules of dimensional error and bending strength variation under the different parameters were summarized,furthermore,the causes were analysed through the proportion of sintering experiment.Using scanning electric microscope observation of sintered parts internal form confirmed the best proportion of PS/GF composite powder.The warping phenomenon in the sintering process were analyzed theoretically and the method of adding the support layer were used to improve it.Finally,the rules of dimensional error and bending strength variation under the different parameters were summarized,furthermore,the causes were analysed through a series of prototyping experiments.The main process parameters(scanning interval,scanning speed and layer thickness)were selected to carry out orthogonal experiment,the best process parameters combination was obtained with variance analysis by dimensional accuracy of the Z direction and bending strength as indicators.Eventually,the formation quality was improved effectively.