System and Method for Powder Bed Fusion Additive Manufacturing with Dynamic Roller Rotational Speed Adjustment

A powder bed fusion additive manufacturing system comprising:

• a build platform on which a substrate is supported;
• an energy generator configured to generate an energy beam directed at the substrate;
• a roller having an actuator system configured to rotate the roller;
• a controller operably connected to the roller and to the energy generator, the controller configured to produce a build object by:
• (i) operating the actuator system based on desired properties of the build object to rotate the roller at a first rotational speed to spread powder particles at a first porosity on the substrate;
• (ii) operating the energy generator to selectively melt the powder particles and portions of the substrate adjacent to the selectively melted powder particles to form a first layer of the build object on the substrate;
• (iii) operating the actuator system based on the desired properties of the build object to rotate the roller at a second rotational speed to spread powder particles at a second porosity on at least one of the substrate and the first layer, the second rotational speed being different from the first rotational speed;
• and (iv) operating the energy generator to selectively melt the powder particles spread at the second porosity to form a second layer of the build object on the at least one of the substrate and the first layer.