Sıcaklık ve Maruz Kalma Süresinin Meşe Odunu Eğilme Özelliklerine Etkisi

Sıcaklık, malzeme özelliklerine ve malzemenin kullanım esnasındaki davranışına etkisi olan çevresel etkenlerden biridir. Bu çalışmada, sıcaklığın ve maruz kalma süresinin ultrasonik dalga hızı, dinamik elastikiyet modülü, eğilmede elastikiyet modülü ve eğilme direncine etkisi boyuna ultrasonik dalga yayımı ve üç nokta eğilme testi ile ortaya konulmuştur. Sonuçlara göre, tüm özellikler yoğun muamele koşullarında düşmüştür. En yüksek düşüş, % 4.7, 16.6, 20.7, 34.1 ve 8.7 ile 210 °C 8 saat muamele sonucu VLL, Edyn, MOE, MOR ve yoğunluk değerlerinde olmuştur. Fakat yoğunluk harici özellikler, 150 °C’ye kadar olan ılımlı sıcaklıklarda maruz kalma süresinin artışı ile birlikte grup içinde artarken (80 °C ve 8 saat için VLL: %12.7, Edyn: %20.2, MOE: %18.1, MOR: %11.7) gruplar arasında düşmüştür. Değişkenler arasındaki Pearson korelasyon katsayıları Edyn-MOE için 0.71’den 0.93’e, Edyn-MOR için 0.47’den 0.85’e, Edyn-VLL için 0.02’den 0.75’e, MOE-MOR için 0.71’den 0.88’e, MOE-VLL için 0.02’den 0.78’e ve MOR-VLL için 0.01’den 0.81’e kadar yayılmıştır. Ayrıca, R2 değerleri 0.7’den 0.9’a kadar

Influence of Temperature and Exposure Duration on the Bending Properties of Oak Wood

Temperature is one of the environmental factors that has influences on the material properties, and its behavior in service life. In this study, effects of temperature and exposure duration on the ultrasound wave velocity, dynamic Modulus of Elasticity, Modulus of Elasticity in bending, and Modulus of Rupture were figured out by the transmission of ultrasound longitudinal wave and three points bending tests. According to results, all determined properties were decreased at intensive treatment conditions. Maximum decreases were 4.7, 16.6, 20.7, 34.1, and 8.7 % at 210 °C 8 h treatments for VLL, Edyn, MOE, MOR, and density, respectively. However, at moderate temperatures up-to 150 °C, properties (except density) were increased (VLL: 12.7%, Edyn: 20.2%, MOE: 18.1%, MOR: 11.7% at 80°C for 8h) with the increase in exposure time within the groups but decreased between the groups. Pearson correlation coefficients between the variables were ranged from 0.71 to 0.93 for Edyn-MOE, 0.47 to 0.85 for Edyn-MOR, 0.02 to 0.75 for Edyn-VLL, 0.71 to 0.88 for MOE-MOR, 0.02 to 0.78 for MOE-VLL, and 0.01 to 0.81 for MOR-VLL. Furthermore, R2 values were ranged from 0.7 to 0.9.

Keywords:

oak, ultrasound bending properties, modulus of elasticity,

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