层厚/支撑角度及后处理对SLA零件性能的影响

Effect of Layer Thickness,Support Angle and Post-processing on Properties of SLA Parts

采用VisiJet~SL Black型光敏树脂,从成型过程及后处理工艺出发,研究了切片层厚、支撑角度对成型件尺寸精度和表面精度的影响及二次固化时间对拉伸性能的影响。结果表明,支撑角度越接近45°,试样尺寸精度越高,小支撑角度大层厚试样会出现上表面隆起现象;层厚越大,试样表面越粗糙;二次固化后的拉伸强度在9.33~22.84 MPa之间,断裂机制均为脆性断裂,二次固化时间为200min时,材料的拉伸强度为20.24 MPa,塑性最好,断裂伸长率最大为3.80%;二次固化时间为250min时,拉伸强度最大为22.84 MPa,但塑性降低。

This article reported an investigation on the accuracy and tensile property derived from the prototyping process and post-processing technology for improvement of the accuracy and mechanical properties of SLA parts.VisiJetSL Black photosensitive resin was employed as a based material to prepare SLA parts.Effects of layer thickness and support angle on the size and surface accuracies of the parts were studied,and influence of post-curing time on their mechanical properties was evaluated.The results indicated that the parts achieved a higher size accuracy when the support angle was close to 45°.A hump phenomenon was observed for the parts with a thick layer at a small support angle.Thicker layer resulted in a rougher surface for the parts.The parts achieved a tensile strength around 9.33~22.84 MPa with a brittle fracture.When the post-curing time was set to 200 min,the parts obtained a best plasticity effect and thus gained the tensile strength of 20.24 MPa and elongation at break of 3.80 % as an optimum value.However,the plasticity became poor for the parts at the post-curing time of 250 mins,although they achieved a maximum tensile strength of 22.84 MPa.