OPTIMIZING ADDITIVE MANUFACTURING OF COCR DENTAL ALLOY: ENHANCED PRODUCTIVITY WHILE MEETING ISO 22674 MECHANICAL REQUIREMENTS

Cosmin COSMA, Stelian LIBU, Alexandru POPAN, Mircea DUDESCU, Nicolae BALC

Abstract


This study investigated the SLM parameter to increase productivity while meeting ISO 22674 mechanical requirements for dental applications (≥500 MPa yield strength, ≥2% elongation). Six parameter sets (M1–M6) were tested. The optimized M5 set (30 µm layer thickness, 85 W laser power, 960 mm/s scan speed, 50 µm hatch spacing) doubled the build-up rate from 0.77 mm³/s to 1.44 mm³/s compared to M1. As-built samples showed 1074–1298 MPa yield strength but only 1.4% elongation. After stress relief treatment (800 °C, 1 h), M5 samples reached 802 MPa yield strength and 2.9% elongation, meeting ISO 22674. Practical validation included 18 dental bridges with proper fit and surface quality. The M5 parameters are compatible with older SLM machines (≤100 W), underscoring the practical relevance and potential impact on productivity.

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References


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