Comb-Tooth Crack Evaluation for Additively Manufactured Parts

The patent introduces a preliminary action by adding a notch to the manufactured object before the additive manufacturing process. This notch serves as a stress concentration point that pre-determines where cracks will form, eliminating the need for post-manufacturing cross-section cutting and polishing to locate cracks. The crack evaluation can be performed directly on the surface, dramatically reducing evaluation time while maintaining accuracy.

The patent segments the evaluation process by dividing the crack evaluation device into multiple comb teeth, where each tooth represents an independent evaluation unit. By counting the number of cracked comb teeth rather than attempting to measure continuous crack patterns, the method achieves quantitative crack sensitivity evaluation while maintaining the simplicity of visual inspection. This segmentation transforms a qualitative visual assessment into a quantitative countable metric.

The patent transitions from evaluating crack patterns in two dimensions (surface visual inspection) to evaluating crack distribution across multiple discrete comb teeth elements. This dimensional change allows the method to detect even subtle cracking in materials less prone to cracking by counting individual tooth failures, thereby expanding applicability to diverse material compositions while maintaining evaluation simplicity.