THE EFFECT OF LASER POWER AND LAYER THICKNESS PARAMETERS ON THE TENSILE STRENGTH AND ELONGATION IN SELECTIVE LASER MELTING PRODUCTION

Abstract

The most widely used additive manufacturing method in dentistry is the selective laser melting (SLM) system. The popularity of SLM systems for the manufacture of cobalt-chromium alloy powders is increasing day by day. The aim of this study is to investigate the effect of changing the laser power and layer thickness parameters during the production process of Co-Cr metal substructures produced by the laser sintering method on the tensile strength and elongation at fracture of the metal substructure. A total of 120 dumbbell-shaped samples were produced with a diameter of 3 mm and a length of 18 mm. The samples were produced at different layer thicknesses and under different laser powers. For 20 and 30 µm layer thicknesses, 4 different laser powers ranging from 50-200 W were produced with the TruPrint 1000 laser metal fusion system and its mechanical properties were tested with the tensile test. Conformity to the normal distribution was evaluated using the Shapiro-Wilk test. The two-way ANOVA method was used to examine the effects of laser power and layer thickness effects and interaction on tensile strength and elongation values, and multiple comparisons were made with Bonferroni test. The variation of laser power and layer thickness in the SLM manufacturing process partially affects the mechanical properties. While laser power and layer thickness affect tensile strength, laser power affect elongation, and the effect of layer thickness on elongation was not found significant.

Keywords

• Co-Cr
• additive manifacturing
• SLM

SEÇİCİ LAZER ERİTME İLE YAPILAN ÜRETİMDE LAZER GÜCÜ VE TABAKALAMA KALINLIĞI PARAMETRELERİNİN ÇEKME KUVVETİ VE KOPMA UZAMASI ÜZERİNE ETKİSİ

Abstract

Diş hekimliği alanında eklemeli üretim yöntemlerinden en yaygın kullanıma sahip olanı seçici lazer eritme sistemidir (SLM). Kobalt-krom (Co-Cr) alaşımlı tozların imalatı için SLM sistemlerinin popülerliği gün geçtikçe artmaktadır. Bu çalışmanın amacı lazer sinterleme yöntemi ile üretilen Co-Cr metal altyapıların üretim sürecinde lazer gücü ve tabakalama kalınlığı parametrelerinin değiştirilmesinin, metal altyapının çekme mukavemeti ve kopma uzamasına etkisinin araştırılmasıdır. Dambıl şekilli toplamda 120 adet numune 3 mm çapında ve 18 mm uzunluğunda üretilmiştir. Numuneler farklı tabakalama kalınlıklarında, farklı lazer güçleri altında üretilmiştir. 20 ve 30 µm tabakalama kalınlıkları için 50-200 lazer gücü arasında değişen 4 farklı lazer gücü TruPrint 1000 lazer metal füzyon sistemiyle üretilmiş ve mekanik özellikleri çekme testiyle test edilmiştir. Normal dağılıma uygunluk Shapiro-Wilk testi ile incelendi. Lazer gücü ve tabakalama kalınlığı etkilerinin ve etkileşiminin çekme mukavemeti ve kopma uzaması değerleri üzerine etkilerini incelemek için İki-yönlü ANOVA yöntemi kullanıldı ve çoklu karşılaştırmalar Bonferroni testiyle gerçekleştirildi.SLM üretim sürecinde lazer gücü ve tabakalama kalınlığının değişimi mekanik özellikleri kısmen etkilemektedir. Lazer gücü ve tabakalama kalınlığı çekme mukavemetini, lazer gücü kopma uzamasını etkilerken tabakalama kalınlığının kopma uzamasına etkisi anlamlı bulunmamıştır.

Keywords

• SLM
• Co-Cr
• eklemeli üretim

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