Vickers Mikro Sertlik Testi Kullanılarak Yaşlı Ahşap Malzemelerin Mekanik Özelliklerinin Belirlenmesi

Year 2019, Volume: 19 Issue: 1, 106 - 115, 27.03.2019

Elif Aşıkuzun , Ümmü Karagöz İşleyen

https://doi.org/10.17475/kastorman.543542

Abstract

Çalışmanın amacı: Bu çalışmada, tarihi ahşap binalardan elde edilen yaşlı ahşabın zaman etkisi altındaki değişimlerinin belirlenmesi amaçlanmıştır.

Çalışma alanı: Deneysel analizde yaşlı ahşap (AW) ve yeni ahşap (NW) kullanılmıştır. Ahşap örneklerinin türü Pinus sylvestris L.’ tir. Yaşlı ahşap 50 yaşın üzerinde olup, Kastamonu'daki tarihi ahşap binalardan elde edilmiştir.

Materyal ve Yöntem: Yaşlı ve yeni ahşap örnekleri zamanın etkisini karşılaştırmak için hazırlanmıştır. Yeni ve yaşlı ahşapların mekanik özellikleri, kristalliği ve mikro yapısı sırasıyla Vickers mikrosertlik, XRD ve SEM cihazları kullanılarak incelenmiştir. Yaşlı ve yeni ahşap malzemenin mekanik ve yapısal özelliklerinde meydana gelen değişimler tespit edilmiştir.

Temel Sonuçlar: Numunelerin mikrosertlik değerleri uygulanan yüke bağlıdır ve yük arttıkça mikrosertlik değeri artmıştır. Meyer kanunu, orantılı numune direnci (PSR), elastik/plastik deformasyon (EPD), Hays-Kendall (HK) yaklaşımı ve çentici kaynaklı yarılma (IIC) modelleri yükten bağımsız mikrosertlik değerlerinin araştırılması için analiz edilmiştir. Sonuç olarak IIC modeli en başarılı model olarak belirlenmiştir

Keywords

Yaşlı ahşap, yeni ahşap, tarihi yapı, kültürel miras, vickers mikrosertlik

Determination of Mechanical Properties of Aged Wood Material Using Vickers Microhardness Test

Abstract

Aim of study: In this study, it was aimed to determine the changes under the influence of time of the age wood obtained from the historical wooden buildings.

Area of study: The aged wood (AW) and new wood (NW) were used in experimental analysis. Wood samples were Pinus sylvestris L. The aged wood was over 50 years old and is derived from the historical wooden buildings in Kastamonu, Turkey.

Material and Methods: The aged and new wood samples were prepared to compare the effect of time. The mechanical properties, crystallinity and microstructure of new and aged wood were investigated by using Vickers microhardness tester, XRD and SEM, respectively. The change in the mechanical and structural properties of the aged and new wood material was determined.

Main results: The microhardness values depended on the applied load and increased with increasing the applied load. Meyer's law, Proportional Sample Resistance, Elastic/Plastic Deformation, Hays-Kendall Approach and Indentation-Induced Cracking models were analyzed for investigation of load independent microhardness values. As a result, IIC model was the most successful model.

Research highlights: It is very important to know the changes that wood has suffered in time in order to conservation of wooden cultural heritage objects and reuse of aged wood.

Keywords: Aged wood, new wood, historical construction, cultural heritage,

Keywords

Aged wood, new wood, historical construction, cultural heritage, vickers microhardness

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