In laser powder bed fusion (LPBF), it’s tempting to assume that increasing laser power will automatically improve part fusion and density. While power is a key parameter, additive manufacturing is highly sensitive to how that energy is applied. Pushing the power too far, especially without adjusting other factors, can backfire. This is where the myth of “more is better” begins to break down.
When energy density surpasses a certain threshold, it can create a phenomenon known as keyholing; a deep, narrow melt pool that traps vapor and forms voids. These gas pockets expand or collapse during solidification, weakening the part from within. The result is internal porosity that’s often invisible externally but drastically compromises fatigue strength, especially in mission-critical components.
Rather than relying solely on power, engineers must consider Volumetric Energy Density (VED) as a composite metric. It combines power, scan speed, hatch spacing, and layer thickness. Each of these parameters influences how energy is distributed across the powder bed. A balanced VED reduces defects while achieving sufficient fusion and mechanical integrity.
Ultimately, the best results come not from brute-force laser settings but from smart calibration. Fine-tuning scan strategies for specific materials and geometries allows you to optimize melt pool behavior without introducing thermal stress or voids. Higher power is just one tool in the box, not a universal fix.