A titanium alloy fuel nozzle additive manufacturing line at an aviation supplier in southern Jiangsu is now fully operational, and during discussions the workshop director directly highlighted the industry's current reality: cost accounting for metal additive manufacturing has long been oversimplified. A PBF machine capable of printing aviation-grade titanium alloy starts at 6 million RMB, superalloy powder costs 2,000 RMB/kg, and a failed build can mean tens of thousands of RMB in losses—not including subsequent non-destructive testing costs. The powder bed fusion process claims a material utilization rate of 90%, but the actual figure is far lower: after accounting for powder scattered in the build chamber, material consumed by support structures, and losses from sieving and contamination removal, only 30%–40% of the total powder input actually ends up in the part. Moreover, after 3–5 powder reuse cycles, sphericity and oxygen content can no longer meet aviation-grade requirements, and the powder can only be downgraded for non-critical structural parts. Post-processing accounts for roughly 70% of the total workflow. When a metal additive part is removed from the machine, only 30% of the full process is complete; it must then go through stress-relief annealing, hot isostatic pressing (HIP), CNC finish machining, fluorescent penetrant inspection, CT scanning, and shot peening. A hydraulic valve block project implemented by a domestic commercial aircraft supplier at the end of 2024 consolidated 17 original parts into a single 3D-printed component, achieving a 30% weight reduction and an 88% improvement in assembly efficiency—but the project took 18 months from start to finish, with over 4 million RMB invested solely in process validation and post-processing parameter development. The HIP parameter window is extremely narrow: too high a temperature causes alloying element diffusion and embrittlement, while too low a temperature leaves porosity unclosed and fatigue strength insufficient. A single parameter often requires hundreds of test specimens to determine accurately. The core obstacle to volume production lies in process consistency control. Under the same equipment, same powder, and same parameters, parts printed on Monday and Friday can differ in mechanical properties by 10%. Workshop temperature and humidity variations, laser head thermal drift, and cumulative recoater blade wear all affect melt pool quality. One research institute printed over 1,200 test specimens to validate the process window, and after replacing the recoater blade on the same model of equipment, still had to run 30 more specimens for performance matching. At the end of 2024, a leading domestic equipment manufacturer launched a new PBF machine featuring real-time melt pool monitoring that reduced process consistency deviation from 12% to within 3%. It has already been deployed at several aviation supplier plants in the Yangtze River Delta, but the system accounts for about 15% of the total equipment price. The aviation plant's line follows this selection principle: parts that can be made by turning, milling, or grinding are not considered for 3D printing; only parts that would require three or more setups, welding, or complex internal channels under conventional processes are included in additive manufacturing cost accounting.