ABSTRACT

Additively manufactured test specimens made of polyamide 12 (PA 12) by Laser Sintering as well as of acrylonitrile butadiene styrene (ABS) by Fused Layer Modelling, were characterised with active thermography directly after manufacturing and after artificial weathering. For this, two different excitation methods (flash and pulse heating) were used and compared, regarding their suitability for the detection of constructed and imprinted defects inside the test specimens. To increase the quality of the thermograms, data processing methods like thermal signal reconstruction (TSR) and Fourier Transformation after TSR were applied. To further investigate the long-term stability of the additively manufactured test specimens towards environmental stress, like UV radiation, heat, humidity, water contact and frost with active thermography, an artificial weathering test over 2000 hours (~3 months) was applied to the specimens. The monitoring of the changes in the optical properties of the weathered plastics was supplemented by spectral reflectance and UV/VIS spectroscopy.

抽象的

在制造后和人工老化后直接用主动热成像技术对由激光烧结的聚酰胺12（PA 12）以及熔融层建模的丙烯腈丁二烯苯乙烯（ABS）制成的增材制造的试样进行表征。为此，使用了两种不同的激发方法（闪蒸和脉冲加热）并进行了比较，关于它们对于检测试样内部构造和压印缺陷的适用性。为了提高温度记录图的质量，应用了数据处理方法，例如热信号重建（TSR）和TSR之后的傅立叶变换。为了进一步研究增材制造的试样对环境应力（如采用主动热成像技术的紫外线辐射，热量，湿度，水接触和霜冻）的长期稳定性，对样品进行了2000小时（约3个月）的人工耐候性测试。光谱反射率和UV / VIS光谱法补充了对风化塑料光学性能变化的监测。