Atık Astragalus Gummifer Kabuğu Takviyeli Polimer Kompozitlerin Dinamik Performansı: Reçine ve Dolgu Oranının Etkisi

Abstract

Bu çalışmada, atık geven kabuğu (Astragalus gummifer – AG) takviyeli polimer kompozitlerin dinamik davranışı üzerinde reçine türünün (epoksi ve doymamış polyester) ve takviye oranının (%40–70 kütlece) etkileri deneysel olarak incelenmiştir. Mekanik karıştırma ve 25 bar basınç altında kürleme yöntemiyle üretilen AGE (epoksi matris) ve AGP (polyester matris) grubu numuneler, serbest titreşim yöntemiyle modal analize tabi tutularak doğal frekans ve sönümleme karakteristikleri belirlenmiştir. Bulgular, epoksi matrisli sistemlerin daha yüksek rijitlik sergileyerek tüm konfigürasyonlarda AGP grubuna göre daha yüksek doğal frekans ürettiğini göstermektedir; en yüksek frekans, %40 AG içeren AGE1 numunesinde 16.78 Hz olarak kaydedilmiştir. Takviye oranının artırılması, sistem kütlesini artırarak her iki grupta da doğal frekansı sistematik olarak düşürmüştür. Sönümleme kapasitesi açısından polyester matris, viskoelastik karakteri nedeniyle epoksiye karşı belirgin bir üstünlük sağlamıştır; %70 AG içeren AGP4 numunesinin sönümleme oranı (%10.31), muadili AGE4 numunesinin (%3.07) yaklaşık 3.36 katı olarak ölçülmüştür. AG takviye oranının artması, arayüzey sürtünme mekanizmalarını tetikleyerek her iki matris sisteminde de sönümleme oranını yükseltmiştir. Sonuçlar, yüksek rijitlik gerektiren yapısal uygulamalar için epoksi matrisin, yüksek titreşim yalıtımı ve akustik sönümleme gerektiren tasarımlar için ise polyester matrisin tercih edilmesi gerektiğini ortaya koymaktadır. Bu çalışma, atık geven kabuğunun ham haliyle dahi sürdürülebilir mühendislik malzemesi geliştirmede işlevsel bir takviye fazı olarak kullanılabileceğini teknik verilerle doğrulamaktadır.

Keywords

• Modal analiz
• Sürdürülebilir kompozitler
• Doymamış polyester
• Atık geven kabuğu

Ethical Statement

Hazırlanan makale için etik kurul iznine gerek yoktur.

Thanks

Yazar, bu çalışmada kullanılan laboratuvar imkânları için Bingöl Üniversitesi'ne ve Atatürk Üniversitesi Mühendislik Fakültesi Makine Mühendisliği Bölümü'ne teşekkür eder.

Dynamic Performance of Waste Astragalus gummifer Bark-Reinforced Polymer Composites: Effect of Resin and Filler Ratio

Abstract

In this study, the effects of resin type (epoxy and unsaturated polyester) and reinforcement ratio (40–70 wt%) on the dynamic behavior of waste Astragalus bark (Astragalus gummifer – AG)-reinforced polymer composites were experimentally investigated. AGE (epoxy matrix) and AGP (polyester matrix) specimen groups, fabricated by mechanical mixing and curing under 25 bar pressure, were subjected to modal analysis using the free vibration method, and their natural frequency and damping characteristics were determined. The findings demonstrate that epoxy-matrix systems exhibit higher stiffness, producing higher natural frequencies than the AGP group across all configurations; the highest frequency was recorded at 16.78 Hz in the AGE1 specimen containing 40 wt% AG. Increasing the reinforcement ratio systematically reduced the natural frequency in both groups by increasing system mass. In terms of damping capacity, the polyester matrix showed a distinct advantage over epoxy due to its viscoelastic character; the damping ratio of the AGP4 specimen containing 70 wt% AG (10.31%) was approximately 3.36 times that of its counterpart AGE4 specimen (3.07%). Increasing the AG reinforcement ratio triggered interfacial friction mechanisms, elevating the damping ratio in both matrix systems. The results indicate that epoxy matrix should be preferred for structural applications requiring high stiffness, while polyester matrix is more suitable for designs requiring high vibration isolation and acoustic damping. This study technically confirms that waste Astragalus bark can serve as a functional reinforcement phase in sustainable engineering material development, even in its raw, unprocessed form.

Keywords

• Modal analysis
• Sustainable composites
• Unsaturated polyester
• Waste AG bark

Ethical Statement

There is no need to obtain permission from the ethics committee for the article prepared.

Thanks

The author would like to thank Bingöl University and the Department of Mechanical Engineering, Faculty of Engineering, Atatürk University for providing laboratory facilities used in this study.

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