Theory 055/Engineering & Materials /Additive manufacturing
Printed Strength Follows the Layer Angle
Each process and powder gets its own anisotropy factors. The angle may unify them.
The anisotropy of additively manufactured parts is set by the angle between the load and the layer plane rather than by the process parameters, so strength should collapse onto a single curve in that angle across machines.
01The evidence
Additive parts show direction-dependent strength, with the weakest direction usually along the build direction, and the magnitude varies between processes.
02The tension
Design allowables are developed per process and per material, which is expensive and does not transfer. The angle is known to matter but is not used as the organising variable.
03The mechanism
Bonding between layers is weaker than bonding within a layer. A load applied at an angle resolves into components along and across layers, and the weaker component dominates failure.
That makes the angle the controlling variable, and predicts that strength should collapse onto a curve in angle that is scaled but not reshaped by material.
04What this is not
Factor-based design tabulates each combination. This predicts a universal angular curve, which transfers across processes.
05Predictions
- P1Strength should collapse onto a curve in load-layer angle.
- P2Different processes should share the shape.
- P3Layer thickness should scale the curve without reshaping it.
06Refutation
Strength varying with process at fixed angle would leave the curves separate.
07What it changes
It would make printed-part design transferable.