Fren balatalarına rafine bor bileşeni ilavesinin mikroyapı, sertlik ve aşınma üzerindeki etkisinin araştırılması
Yükleniyor...
Tarih
2024-12-24
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Batman Üniversitesi Lisansüstü Eğitim Enstitüsü
Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
Bu tez çalışmasında, fren balatalarına rafine bor bileşeni ilavesinin mikroyapı, sertlik ve aşınma özellikleri üzerindeki etkileri incelenmiştir. Çalışmada kullanılan ana malzemeler arasında novolak reçine, bakır, alümina, grafit, pirinç, zirkonyum silikat, kalsiyum sülfat, çinko sülfat ve baryum sülfat yer almakta olup, bunlara ek olarak borik asit ve boraks dekahidrat tozları belirli ağırlık oranlarında balata karışımına dahil edilmiştir. Malzeme formülasyonunda, baryum sülfat toplam ağırlığın %1,25, %2,5, %5, %10 ve %20 oranlarında azaltılmış ve yerine borik asit ve boraks dekahidrat tozları eklenmiştir. Tartım işlemleri sonrası tüm malzemeler, mekanik bir karıştırıcı ile karıştırıldıktan sonra 30 mm çapındaki kalıplara yerleştirilerek 10 MPa basınç ve 140 °C sıcaklık altında 30 saniye ile preslenmiştir. Her formülasyon için üç adet numune üretilmiştir. Üretilen numunelerin mikroyapıları optik mikroskopla incelenmiştir. Ayrıca numunelerin teorik ve yığınsal yoğunlukları hesaplanmış ve bu yoğunluk değerlerine bağlı olarak porozite oranları belirlenmiştir. Daha sonra Brinell sertlik testi ile sertliği belirlenen numuneler, 18 N yük altında 400 m, 800 m ve 1200 m kayma mesafelerinde aşınma testine tabi tutulmuştur. Mikroyapı analizleri, numunelerin gözenekli bir yapıya sahip olduğunu göstermiştir ve yapıdaki bor bileşeni oranı arttıkça gözenekliliğin arttığı görülmüştür. Bu durum, yoğunluğun azalmasına neden olmuştur. Rafine bor ürünü kullanılan numunelerde, başlangıçta artan takviye oranı ile sertlik değerinin yükseldiği, ancak belirli bir takviye oranının üzerine çıkıldığında sertlik değerinde düşüş tespit edilmiştir. Borik asit bileşeninin kullanıldığı numunelerde %2,5 takviye oranından, boraks dekahidrat bileşeninin kullanıldığı numunelerde ise %5 takviye oranından en yüksek sertlik değerleri elde edilmiştir. Öte yandan sertlik ve aşınma arasında doğrusal bir ilişki olduğu görülmüştür. En yüksek sertliğe sahip numunelerin daha düşük aşınma hacmine ve oranına sahip olduğu gözlemlenmiştir. Ayrıca balata numunesine eklenen rafine bor bileşeninin sürtünme katsayısını da arttırdığı tespit edilmiştir.
In this thesis, the effects of adding refined boron compound to brake pads on microstructure, hardness, and wear properties are investigated. The primary materials used in the study include novolac resin, copper, alumina, graphite, brass, zirconium silicate, calcium sulfate, zinc sulfate, and barium sulfate. Additionally, boric acid and borax decahydrate powders are incorporated into the brake pad mixture in specific weight ratios. In the material formulation, barium sulfate was reduced by 1.25%, 2.5%, 5%, 10%, and 20% of the total weight, and boric acid and borax decahydrate powders were added in place. After weighing, all materials were mixed with a mechanical mixer, placed into 30 mm diameter molds, and pressed for 30 seconds under 10 MPa pressure at 140°C. Three samples were produced for each formulation. The microstructures of the produced samples were examined using an optical microscope. Additionally, the theoretical and bulk densities of the samples were calculated, and porosity rates were determined based on these density values. The samples' hardness was determined using the Brinell hardness test, and wear tests were conducted under an 18 N load at 400 m, 800 m, and 1200 m sliding distances. Microstructure analysis revealed that the samples had a porous structure, and it was observed that as the proportion of boron compound in the structure increased, the porosity also increased. This caused a decrease in density. In the samples with refined boron products, hardness values initially increased with the increasing reinforcement ratio, but a decrease in hardness was detected once a certain reinforcement ratio was exceeded. The highest hardness values were obtained at a 2.5% reinforcement ratio for samples with boric acid and at a 5% reinforcement ratio for samples with borax decahydrate. Furthermore, a linear relationship between hardness and wear was observed. It was noted that the samples with the highest hardness had lower wear volume and rate. Additionally, it was also found that the addition of refined boron compound to the brake pad sample increased the friction coefficient.
In this thesis, the effects of adding refined boron compound to brake pads on microstructure, hardness, and wear properties are investigated. The primary materials used in the study include novolac resin, copper, alumina, graphite, brass, zirconium silicate, calcium sulfate, zinc sulfate, and barium sulfate. Additionally, boric acid and borax decahydrate powders are incorporated into the brake pad mixture in specific weight ratios. In the material formulation, barium sulfate was reduced by 1.25%, 2.5%, 5%, 10%, and 20% of the total weight, and boric acid and borax decahydrate powders were added in place. After weighing, all materials were mixed with a mechanical mixer, placed into 30 mm diameter molds, and pressed for 30 seconds under 10 MPa pressure at 140°C. Three samples were produced for each formulation. The microstructures of the produced samples were examined using an optical microscope. Additionally, the theoretical and bulk densities of the samples were calculated, and porosity rates were determined based on these density values. The samples' hardness was determined using the Brinell hardness test, and wear tests were conducted under an 18 N load at 400 m, 800 m, and 1200 m sliding distances. Microstructure analysis revealed that the samples had a porous structure, and it was observed that as the proportion of boron compound in the structure increased, the porosity also increased. This caused a decrease in density. In the samples with refined boron products, hardness values initially increased with the increasing reinforcement ratio, but a decrease in hardness was detected once a certain reinforcement ratio was exceeded. The highest hardness values were obtained at a 2.5% reinforcement ratio for samples with boric acid and at a 5% reinforcement ratio for samples with borax decahydrate. Furthermore, a linear relationship between hardness and wear was observed. It was noted that the samples with the highest hardness had lower wear volume and rate. Additionally, it was also found that the addition of refined boron compound to the brake pad sample increased the friction coefficient.
Açıklama
Anahtar Kelimeler
Fren Balatası, Bor Bileşeni, Mikroyapı, Sertlik, Sürtünme-Aşınma, Brake Pad, Boron Component, Microstructure, Hardness, Friction-Wear
Kaynak
WoS Q Değeri
Scopus Q Değeri
Cilt
Sayı
Künye
Gündüz, N. (2024). Fren balatalarına rafine bor bileşeni ilavesinin mikroyapı, sertlik ve aşınma üzerindeki etkisinin araştırılması. (Yayınlanmamış Yüksek Lisans Tezi). Batman Üniversitesi Lisansüstü Eğitim Enstitüsü, Batman.
