以聚苯乙烯(PS)为原材料的选区激光烧结（SLS）制件具有成型精度高、成型周期短等优点，被广泛应用于快速熔模铸造领域，但因其烧结强度低，不适用于大型复杂零件或对强度有更高要求的原型件、功能件的成型。本文旨在提高PS制件的强度，对聚苯乙烯/碳纤维（PS/CF）复合材料的制备和SLS成型机理、工艺参数的范围与工艺参数优化、气相沉积碳纤维增强聚苯乙烯等问题进行了系统的理论分析与实验研究，最终有效提高了PS制件的烧结强度，这对于拓宽PS制件的应用范围有实际意义。 首先针对SLS成型工艺特点，选择满足SLS工艺要求的一种CF粉末作为增强剂，运用机械混合法制备含CF质量分数10%的PS/CF复合材料，通过热重实验测定了复合材料的分解温度，从材料与激光的热作用过程分析了复合粉末SLS成型机理，并结合SLS工艺对铺粉性能的要求分析了复合粉末的铺粉性能，为后续烧结实验奠定基础。 然后通过一系列烧结实验，确定了适合PS/CF复合材料的工艺参数范围，总结并分析了扫描速度和层厚两个主要工艺参数对PS/CF制件强度与精度的影响规律及成因，计算了复合材料的烧结件密度。选取主要工艺参数（扫描速度、预热温度、层厚）进行三因素三水平正交实验，采用极差分析法，以制件的强度为评价指标，得到使强度较高的工艺参数组合以及各工艺参数对制件强度的影响程度，有效地提高了PS制件的强度。利用扫描电镜观察了制件的内部形貌，分析进一步提高强度的突破点。 最后从增加复合材料界面结合力出发，对CF材料做气相沉积处理，制备气相沉积处理后的PS/CF复合材料，再进行烧结实验，验证其增强效果。改变气相沉积CF与PS的配比，分析增强剂含量对制件强度的影响，最终得到强度较高时的材料配比为10wt.%气相沉积PS/CF，弯曲强度达9.94MPa，比纯PS制件提高约72.3%。

There are many advantages for PS (Polystyrene) parts manufactured by SLS (selective laser sintering), such as high molding precision and short molding period, etc. Therefore，it is widely used in rapid investment casting field. While, due to it’s low intensity, it could hardly be used in sintering complex parts of large size, as well as prototype models or function parts of higher intensity requirements. This work aimed at improving the bending strength of PS sintered parts. Composites of CF (carbon fiber) reinforced PS were prepared, of which mechanism in SLS was analyzed. The scope of each process parameter and the optimization of these parameters were studied through prototyping experiments. Moreover, PS reinforced with CF treated with vapor-deposition method was presented. The experiments data shows that the bending strength of PS sintered parts was improved effectually, which has practical significance in broadening the applications of PS parts. First of all, one kind of CF powder was designated as the reinforcing agent matched with the requirements of SLS process. Composites of PS reinforced with 10wt.% CF were prepared with mechanical mixing method. The decomposition temperature of PS/CF composites was measured through TG(Thermo-gravimetric) experiments, and it’s molding mechanism based on the SLS was analyzed in term of thermal process between the composites and the laser. On the other hand, the spreading performance of powders was analyzed according to the requirements of SLS process, which established a theoretical foundation of subsequent sintering experiments. Secondly, the scope of each technical parameter matched with PS/CF composites was acquired through a series of molding experiments. The rules of intensity variation, density change and the dimensional error under the interaction of main parameters (scanning speed and layer thickness) were summarized, the causes of which were analyzed as well. Furthermore, the main process parameters (scanning speed, preheating temperature and layer thickness) were selected to carry out orthogonal test. Both the optimum technological conditions and how important each parameter is to bending strength were determined, using variance components method by intensity as indicators. The formation strength of PS was improved effectively. At last, the internal morphology of the parts was observed by scanning electric microscope, the key to further improving the bending strength were acquired. Finally, in order to fortify the combination power of phase surface, the CF was treated with vapor deposition method. Composites of PS reinforced with vapor deposited CF were prepared. Then prototyping experiments were carried out to demonstrate whether it is work to reinforcement. At last, the influence on formation intensity owe to the content of reinforcing agent was analyzed by changing mixing ratios. The results show that the optimal ratio is composites of PS reinforced with 10wt.% vapor deposited CF, of which the bending strength is up to 9.94MPa, about 72.3 percent higher than that of PS.