System and methods for printing defect detection

A method of detecting defects during metal additive manufacturing, comprising the steps of:

• spreading a metal powder on a powder bed of a metal additive manufacturing system and depositing a predetermined pattern of binder to the metal powder to form a layer of a green part;
• generating a first illumination condition and capturing a first image of the illuminated layer of the green part with a first imaging device;
• generating a second illumination condition and capturing a second image of the illuminated layer of the green part with a second imaging device;
• and
• comparing the first image and second image to at least one of each other, a design file and a third image and identifying a first defect in the layer of the green part, wherein the defect is one of a blister, a divot, a smear, beading and a jet-out condition.

A method of identifying and clearing clogged jetting orifices in a binder jetting metal additive manufacturing system, comprising the steps of:

• spreading from a printhead a metal powder on a powder bed of a metal additive manufacturing system and depositing a predetermined pattern of binder to the metal powder to form a layer of a green part;
• illuminating the layer of the green part with a high angle light source;
• capturing an image of the illuminated layer of the green part with an imaging device;
• identifying areas of unbound powder according to the brightness an amount of reflected light;
• comparing the areas of unbound powder to a design file and identifying a defect indicating a jet-out condition;
• and
• subjecting the printhead to a maintenance cycle.