Approximation of absolute surface temperature measurements of powder bed fusion additive manufacturing technology using in situ infrared thermography

Thermal evolution behavior and fluid dynamics during laser additive manufacturing of Al-based nanocomposites: Underlying role of reinforcement weight fraction

“…Presently, monitoring has been commercially applied to the newest laser processes, including additive manufacturing and laser welding. [14][15][16] Charged-couple device (CCD) or complementary metal-oxide semiconductor (CMOS) cameras with high resolution are usually used for process monitoring and real-time control. However, the dimensions of laser-induced melt pool are extremely small and, meanwhile, the duration of laser beam on any powder particle is considerably short, which is typically between 0.5 and 25 ms.…”

Four-color imaging pyrometer for mapping temperatures of laser-based metal processes

“…Infrared cameras also have limitations in this environment because of the low and changing emissivity of the hot metal. The same is true with power-fed and powder-bed additive manufacturing techniques [4][5][6][7] . Without accurate knowledge of the emissivity, the measured temperatures are apparent (or relative) temperatures and not true (or absolute) temperatures.…”

Preparation of weak-textured commercially pure titanium by electron beam melting

“…The martensite start temperature (M S ) of CP-Ti is as high as 850 °C [34], rather higher than the preheating temperature (650 °C in this case), and the preheating temperature roughly corresponds to the surface temperature of powder bed where melting of powder occurs [35]) as well as to the post-solidification sample temperature. In addition, the cooling rate just after the powder melting stage in the EBM fabrication can be assumed to be between 10 3 −10 5 K s −1 [30].…”