Effect of Pulse Repetition and Peak Power of Nd:YAG Laser for Surface Treatment on Ti–6Al–4V Alloy

Abstract

Titanium and titanium alloys have led to a diversified range of successful application in various fields including the medical and aerospace industry due to the high strength to weight ratio and excellent corrosion resistance. Several techniques have been considered to achieve reliable welds and treatments for the fabrication of components in these industries. Among these techniques, laser welding can provide a significant benefit for the welding of titanium alloys because of its precision and rapid processing capability. The Nd:YAG laser parameters, such as pulse shape, energy, duration, welding speed, peak power and frequency of repetition, influence directly or synergistically the quality of pulsed seam welds and it’s morphology. In this study, 1.5 mm thick Ti6Al4V Titanium alloy sheet surface have been treated by SigmaLaser®300 type Nd:YAG pulsed laser. The influence of peak power and pulse frequency on weld quality, seam morphology and effects to the surface have been investigated. The seam quality has been characterized in terms of weld morphology and micro hardness.

Keywords

• YAG laser
• Surface treatment
• Ti6Al4V alloy

Nd:YAG Lazer ile Ti–6Al–4V Alaşımı Yüzey İşlemlerinde Atış Tekrarı ve Pik Gücünün Etkisi

Abstract

Titanyum ve Titanyum alaşımları, yüksek mukavemet, düşük ağırlık oranı ve mükemmel korozyon direnci sebebiyle, medikal ve havacılık endüstrisi dahil olmak üzere birçok alanda başarıyla kullanılmaktadır. Bu alanlarda yapılan üretimler için uygulanan kaynak ve iyileştirme işlemleri için birçok teknik mevcuttur. Bu teknikler arasında, lazer kaynağı hassas ve hızlı işlem kabiliyeti sayesinde Titanyum alaşımları için çok önemli avantajlar sağlamaktadır. Darbe ya da atış şekli, enerji, süre, kaynak hızı, pik gücü ve frekans gibi Nd:YAG lazer parametereleri, doğrudan ya da dolaylı olarak kaynak dikiş kalitesini ve morfolojisini etkilemektedir. Bu çalışmada, 1.5 mm kalınlığında Ti6Al4V Titanyum alaşımı levha yüzeyi SigmaLaser®300 Nd:YAG tipi lazer kaynak cihazıyla işlenmiştir. Pik gücü ve frekans değerlerinin kaynak kalitesine, dikiş morfolojisine ve numune yüzeylerine etkisi incelenmiştir. Dikiş kalitesi, morfoloji ve mikro sertlik değerleri bakımından karekterize edilmiştir.

Keywords

• YAG lazer
• Yüzey iyileştirme
• Ti6Al4V alaşımı

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