Study On The Laser Sintering Process Of Carbohydrate-based Material

Selective Laser Sintering (SLS) is a Proven advanced manufacturing technology of theRapid Prototyping (RP) methods. Now it attracts extensive attention because of the abundantraw materials, high manufacturing flexibility and no supporting during the process. But thehigh Price of the raw materials and no-recycling restrict its developing and popularizing.Based on having reviewed the development status and trend, this paper proposed a kindof cheap carbohydrate-based material as the raw material of SLS, Which is greenenvironmental protection,degradable and recyclable.The use of the carbohydrate-basedmaterial successfully making three-dimensional model, which has a certain function strength,the model can be used as a substitute for manufacturing activity of the implant, and can alsobe used for biological manufacturing and artificial bone in medical field.According to the characteristics of the technology of selective laser sintering, thecarbohydrate-based material is used on laser sintering in this study.Use the method ofsingle-line scanning selected the sucrose as the molding material first. Then we crushed thematerial for material designed.Through orthogonal experimental design, sucrose was studiedpreliminary sintering, the precision and surface quality of the model is poor. Therefore, thecarbohydrate-based materials for laser sintering is re-examined, use the sugar mixed withstarch as sintered materials. Reasonable proportion of the mixed powder was studied in twomaterial powder material, use the test methods of XRD, DSC/TG et clarify the mechanismof forming mixed powder sintering. This paper studied the impact of different technologicalparameters on the sintering processing and the molding properties, including preheatingtemperature, laser power, scanning speed and interval and thickness of stratum. It got a set ofoptimized parameters, which can be used in SLS for carbohydrate-based material.At last, because of the large porosity and the low strength, this paper studied the post processing.By testing to determine the suitable temperature of drying and the appropriatelength of drying time for treatment process. Analysis of the factors which affecting theaccuracy of carbohydrate-based material model，and put forward the improvement method.By the testing of the parts before and after post processing, it got that the post processingcould improve the mechanical properties and surface quality greatly.