气压熔融挤压快速成形材料及成形工艺研究

为了拓宽气压熔融挤压快速成形工艺的应用领域,开发了可应用于气压熔融挤压快速成形的改性石蜡材料,并对成形工艺进行了研究.研究结果表明,改性石蜡熔融挤丝的黏度随硬脂酸镁含量的增加而增大,当挤丝直径增加时,丝径的均匀程度降低,使成丝性能也降低.当硬脂酸镁的质量分数降低至1/10时,材料黏度降低,丝材之间表现出脱黏现象,从而影响了成形性能.实验表明,石蜡与硬脂酸镁的质量比为8:1,通过建立的熔融挤丝宽度与熔融挤出丝速率、扫描速度和分层厚度之间的数学模型,得到了挤出丝速率、扫描速度和分层厚度相匹配的工艺参数,并验证了挤丝宽度和扫描间距对制件质量的影响.

Material and Prototyping Process in Air Pressure Fused Deposition Manufacturing

To extend the application area of the air pressure fused deposition manufacturing (FDM),the modified paraffin is developed and the prototyping performance of the air pressure FDM is investigated.The increased results show that the viscosity of modified paraffin melt increases with research content of magnesium stearate increased.The increment of the modified paraffin melt viscosity contributes to the larger diameter and less uniformity of the wire.When the content Of magnesium stearate decreases to 10:1,it can be observed that dehiscence appears because of the decline of the viscosity of modified paraffin.The suitable weight ratio of paraffin and magnesium stearate can be determined as 8:1.The mathematical model of a wire width with wire melt extrusion rate,scanning speed and thickness is established,and the matching parameters of melt wire extrusion speed and scanning speed and coating thickness are given.The influence of the wire width and scanning distance on the quality of workpiece is verified by the experiments.