Isıl işlemin orta yoğunlukta lif levha (MDF) üzerindeki etkilerinin araştırılması

Abstract

Özellikle orta yoğunlukta lif levha (MDF) gibi malzemeler yüksek mukavemet, homojen yapı ve kolay işlenebilirlik gibi avantajlara sahip olmakla birlikte suya karşı hassasiyet ve formaldehit emisyonu gibi dezavantajlara sahiptir. Bu dezavantajları en aza indirmek ve malzemenin dayanıklılığını artırmak için ısıl işlem gibi yöntemler kullanılmaktadır. Bu çalışma, farklı sıcaklıklarda ısıl işlemin MDF numunelerinin suda şişme ve formaldehit emisyonu değerleri üzerindeki etkisini belirlemek amacıyla gerçekleştirilmiştir. Deneylerde 18 mm kalınlığında lif levhalar kullanılmıştır. Bu çalışmada kullanılan lif levha numuneleri 120 °C, 150 °C ve 180 °C'de sırasıyla 2, 4 ve 6 saat bekletilmiştir. Isıl işlemde artan süre ve sıcaklıkla birlikte suda şişme ve formaldehit emisyon değerlerinin azaldığı gözlemlenmiştir.

Keywords

• Isıl işlem
• MDF
• Vida çekme
• Suda şişme
• Formaldehit emisyonu

Investigation of the effects of heat treatment on medium density fiberboard (MDF)

Abstract

In particular, materials such as medium density fiberboard (MDF) have advantages such as high strength, homogeneous structure and easy processability, but disadvantages such as sensitivity to water and formaldehyde emission. To minimize these disadvantages and increase the durability of the material, methods such as heat treatment are used. This study was carried out to determine the effect of heat treatment at different temperatures on water swelling and formaldehyde emission values of MDF samples. Fiberboards with a thickness of 18 mm were used in the experiments. The fiberboard samples used in this study were kept at 120 °C, 150 °C and 180 °C for 2, 4 and 6 hours respectively. It was observed that water swelling and formaldehyde emission values decreased with increasing time and temperature in heat treatment.

Keywords

• Heat treatment; MDF
• Screw withdrawal
• Swelling in water
• Formaldehyde emission

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