The prediction of mechanical properties of wood-based composites with vibration NDE method
Bu çalışmada kontrplak, yongalevha ve orta yoğunlukta liflevha (MDF) örneklerinde vibrasyon frekansı yöntemi ile tahribatsız olarak tespit edilen dinamik elastikiyet modülü (MOEd) değerleri ile tahribatlı testlerden elde edilen mekanik özellikler arasındaki ilişkiler araştırılmıştır. Sonuç olarak yongalevhalarda hem boyuna vibrasyon hem de eğilme vibrasyonunda MOEd ile statik eğilme direnci (MOR) ve statik eğilmede elastikiyet modülü (MOES) değerleri arasında kuvvetli korelasyonlar tespit edilmiştir. Aynı şekilde MDF örneklerinde de MOEd ile MOES ve MOR arasında iyi korelasyonlar bulunmuştur. Kontrplaklarda ise uzun eksenel paralel yönde MOES ve MOR ile MOEd arasındaki ilişkiler Kabul edilebilir niteliktedir. Ancak uzun eksenel dik yönde elde edilen sonuçlar tatminkâr değildir. Son olarak yongalevha ve MDF'lerin yapışma direnci ile MOEd arasında bir korelasyon tespit edilememiştir.
Odun esaslı levhalarda mekanik özelliklerin vibrasyon tahribatsız değerlendirme yöntemi ile belirlenmesi
In this study, dynamic modulus of elasticity (MOEd) of plywood, particleboard and medium density fiberboard (MDF) were determined by using a Fast Fourier Transform (FFT) analyzer and compared to their mechanical properties obtained from the same specimens. It was revealed that strong correlations between MOEd and static bending properties (MOES, MOR) were found in both longitudinal and bending vibration for particleboard. There were also good correlations between MOEd and bending properties of MDF. The MOEd in longitudinal and bending vibration is acceptable to predict the bending properties of plywood in parallel direction to long axis. However poor correlations were found between MOEd and IB in particleboard and MDF.
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- ISSN: 0535-8418
- Yayın Aralığı: 2
- Yayıncı: Prof.Dr.Murat Demir