Compact absorptivity measurement system for additive manufacturing

A powdered bed fusion additive manufacturing (PBFAM) apparatus comprising:

• a container for holding a quantity of powdered material, the container having a bottom wall for supporting the quantity of powdered material thereon, the bottom wall being constructed of the same material as the powdered material;
• a plurality of thermocouples having portions extending into the bottom wall of the container and adapted to sense a temperature of the container;
• a thermo-isolated holder for holding the container and made from a metal selected to minimize conductive cooling of the quantity of powdered material;
• a laser configured to generate an optical beam directed at the powdered material held by the container, the optical beam being sufficient in intensity to melt the powdered material;
• and
• a controller in communication with the thermocouples and configured to determine an absorptivity of the powdered material based on information received from the thermocouples, while the powdered material is being melted, wherein the controller is configured to use the determined absorptivity to adjust an output power of the laser while carrying out a PBFAM operation.

A method for performing powdered bed fusion additive manufacturing (PBFAM), the method comprising:

• using a container to hold a quantity of powdered material, the container having a bottom wall for supporting the quantity of powdered material thereon, the bottom wall being constructed of the same material as the powdered material;
• directing an optical beam at the powdered material held by the container, which is sufficient in temperature to melt the powdered material;
• while the powdered material is being melted, sensing a temperature of a portion of the container;
• and
• using a controller to receive the sensed temperature and to determine an absorptivity of the powdered material while the powdered is being melted;
• and
• using the controller to consider the determined absorptivity of the powdered material and to control a power output for the optical beam in real time as the optical beam is melting the powdered material to carry out a PBFAM operation.