While the heat input from the electron beam is relatively flat, the distribution of subsurface cooling channels and the design of individual elements of the sample leads to significant surface temperature distortions in the sample material.
Measurements of the temperature and distortion evolution during laser powder bed fusion (LPBF) are taken as a function of time.
Therefore, an enclosed instrumented system is designed to allow for the in situ measurement of temperature and distortion in an LPBF machine without the need for altering the machine or the build process.
The design requirements consider all influencing elements analysis such as throttle level angle (TLA) movement, ambient temperature, inlet distortion, customer bleeding, power extraction, manufacturing/rigging/controlling tolerances as well as the critical engine condition analysis and pass/fail criteria for measuring design.
A calibration method is proposed to eliminate the temperature-dependent distortion of microwave signals by the microwave-transparent walls of the furnace, and the errors caused by the wall position variations as well.
A method used to determine whether plastics should be described as high-temperature thermoplastics, that is, those capable of being used at ≥150 °C, based on values of heat distortion temperature and continuous use temperature, has been proposed.
Since use-temperature range is one of the most important parameters for engineering polymers, heat distortion temperature (HDT) and glass transition temperature (Tg) of the nanocomposites are analyzed in detail.
Time resolved photocrystallographic studies of the copper analogue have observed similar structural distortions in the excited state, confirming the temperature induced structural distortion is directly linked to the change in emission spectrum.
Both octyl and anhydride treated glass fibers improve the heat distortion temperature such that most of the high temperature stiffness that is lost on addition of EPR-g-MA is regained by adding glass fibers.
The heat distortion temperature (Th) and density of network polyimide films increased and then levelled off with increasing post-polymerization temperature and time.
