CAJ | 학술논문

对聚苯乙烯(PS)粉在激光功率20 W、预热温度70℃、扫描间隔0.30 mm等工艺参数下，研究了扫描速度和层厚对烧结试样长度、宽度、高度相对误差及孔隙率等的影响，并在电镜下观察了烧结试样微观组织，对工艺参数进行优化。结果表明：PS粉烧结时，在不同工艺参数下会分为熔融区和微熔区，熔融区和微熔区烧结件长和宽均由于收缩变形而小于理论值；在熔融区，随着扫描速度和层厚的增大，长、宽尺寸精度越来越高；在微熔区，长、宽尺寸精度变化不大，同时试样由过深烧结到烧结不足，高度值由大变小，试样孔隙率逐渐增大。扫描速度对孔隙率影响较大，分层厚度对孔隙率影响较小，确定层厚在0.20～0.22 mm、扫描速度在2100 mm／s为最佳烧结工艺参数。
대취분을희(PS)분재격광공솔20 W、예열온도70℃、소묘간격0.30 mm등공예삼수하，연구료소묘속도화층후대소결시양장도、관도、고도상대오차급공극솔등적영향，병재전경하관찰료소결시양미관조직，대공예삼수진행우화。결과표명：PS분소결시，재불동공예삼수하회분위용융구화미용구，용융구화미용구소결건장화관균유우수축변형이소우이론치；재용융구，수착소묘속도화층후적증대，장、관척촌정도월래월고；재미용구，장、관척촌정도변화불대，동시시양유과심소결도소결불족，고도치유대변소，시양공극솔축점증대。소묘속도대공극솔영향교대，분층후도대공극솔영향교소，학정층후재0.20～0.22 mm、소묘속도재2100 mm／s위최가소결공예삼수。
Under the 20 W of laser power,0.30 mm of scanning interval and 70℃ of preheating temperature,the effect of thic-kness of layers and scanning speed on the sample length’relative error,width’relative error,height’relative error and the porosity through sintered PS powder was studied,the structure of samples in SEM was observed. The process parameters were optimized .The results show that under different process parameters,the sintering results would be divided into the molten zone and the micro-molten zone,the values of length and width in the molten zone and the micro-molten zone are less than the theoretical value due to deformation of shrinkage.In the molten zone,with the increase of scanning speed and thickness of layers,the length’precision and width’precision are higher and higher. In the micro-molten zone,the changes of the length’precision and width’precision are very small. With the increase of scanning speed and thickness of layers,the process range from deep sintering to inadequate sintering, at the same time,sample porosity increases gradually. Scanning speed’effect on porosity is larger,thickness of layers’effect on porosity is small. With the layer thickness of 0.20~0.22 mm,and scanning speed of 2 100 mm/s,the sintered parts has a good quality.