Cross-hatch (ASTM D3359) is good for thin films and quick screening, but has poor discrimination on thick, high-adhesion systems — everything passes.
Pull-off (ASTM D4541) quantifies adhesion and shows the failure locus. Cohesive failure is better than interfacial failure.
Boiling water (e.g. 100℃ / 2 h) and salt spray (ASTM B117) reveal interfacial hydrolytic stability. Judging by initial adhesion alone is a serious misjudgement.
Film thickness, cure energy, dwell time and substrate preparation must be fixed, otherwise data are not comparable.
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