砂型3D打印设备快速固化方法的研究及应用

Research and application of rapid solidification methods for sand 3D printing equipment

相比于传统的铸造用呋喃树脂,酚醛树脂、无机树脂等粘结剂具有诸多优点,是一种较为理想的铸造用粘结剂,但与此同时,该类粘结剂存在常温下难以固化的问题,需要在高温条件下,快速蒸发粘结剂内部的水分,才能提高砂型固化的速度。结合铸造砂型3D打印机的成型原理及设备结构,考虑从打印设备自身实现砂型的快速固化,具体可以从5个方面来提高砂型的固化速度:一是提高粘结剂的温度;二是提高砂子的温度;三是在铺砂器上安装红外加热灯管,对砂面进行烘烤,提高砂面的温度,加速粘结剂中水分的蒸发;四是设计一种带加热盘管的特殊工作箱结构,在打印过程中,随着打印砂型的不断堆叠,对已成型的砂型进行持续性加热,快速提高砂型固化速度;五是控制打印室内部的环境温湿度。

By comparing to traditional furan resin for casting,phenolic resin,inorganic resin and other binders have many advantages as the ideal casting binder.However,at the same time,this type of binder has the problem of being dfficult to solidify at room temperature.It is necessary to quickly evaporate the moisture inside the binder under high temperature conditions to improve the speed of sand mold solidification.Combining the molding principle and equipment structure of the casting sand 3D printer,the rapid solidification of the sand mold has been considered from the printing equipment itself.The solidification speed of the sand mold has been improved from five aspects:firstly,increasing the temperature of the adhesive;secondly,increasing the temperature of the sand;thirdly,installing infrared heating lamps on the sand spreader to bake the sand surface to increase the temperature of the sand surface and accelerate the evaporation of moisture in the binder;fourthly,designing a special working box structure with heating coils,during the printing process,as the printing sand molds are continuously stacked,the formed sand molds are continuously heated to quickly improve the solidification speed of the sand molds;at last,controlling the environmental temperature and humidity inside the printing room.