Microstructural Impact on Crack Resistance in Heavy-Duty Vehicle Brake Discs

Zehra Çınarcık; Bora Güntay

Makale detayları

Microstructural Impact on Crack Resistance in Heavy-Duty Vehicle Brake Discs

Yazarlar:

Zehra Çınarcık | Bora Güntay

Yayıncı:

Gazi University

Ana Başlıklar:

Malzeme Tasarım ve Davranışları

Dergi:

Gazi Üniversitesi Fen Bilimleri Dergisi Part C: Tasarım ve Teknoloji Vol.12 Issue 4, pp.913-924

Belge Tipi:

Makale

Yayın Tarihi:

12/2024

Belge Dili:

Türkçe

Document ID (Org No.):

2001337746

pISSN:

2147-9526

Anahtar kelimeler:

Özet:

 This study aims to comprehensively examine the microstructure of brake discs used in heavy-duty vehicles and its impact on crack resistance, with the goal of enhancing this resistance. In the initial phase, a brake disc sample exhibiting premature crack formation during inertia dynamometer testing was analyzed. Microstructural analysis revealed various defect modes such as non-homogeneous structure and nitrogen porosity within the material. These defect modes were found to adversely affect the crack resistance of the brake disc. To address these issues and improve the microstructural integrity of the material, a series of corrective measures were implemented. These included increasing the feeder inlet numbers during the casting process, optimizing the gating system design, and applying zirconium inoculation. Increasing feeder inlets and improving gating system design improved material flow, resulting in a more homogeneous structure, while zirconium inoculation helped reduce microstructural defects. Following these corrective actions, a second brake disc sample was produced. Observations during inertia dynamometer tests indicated a significant improvement in crack resistance for the new sample. Microstructural analyses confirmed that the implemented measures enhanced material homogeneity and largely eliminated nitrogen porosities. Consequently, the improved microstructure and increased crack resistance of the second sample were verified. This study highlights the critical impact of microstructural characteristics of brake discs on mechanical performance and demonstrates how microstructural improvements can enhance crack resistance. It underscores the importance of microstructural controls and process enhancements in increasing the reliability of brake discs.

 This study aims to comprehensively examine the microstructure of brake discs used in heavy-duty vehicles and its impact on crack resistance, with the goal of enhancing this resistance. In the initial phase, a brake disc sample exhibiting premature crack formation during inertia dynamometer testing was analyzed. Microstructural analysis revealed various defect modes such as non-homogeneous structure and nitrogen porosity within the material. These defect modes were found to adversely affect the crack resistance of the brake disc. To address these issues and improve the microstructural integrity of the material, a series of corrective measures were implemented. These included increasing the feeder inlet numbers during the casting process, optimizing the gating system design, and applying zirconium inoculation. Increasing feeder inlets and improving gating system design improved material flow, resulting in a more homogeneous structure, while zirconium inoculation helped reduce microstructural defects. Following these corrective actions, a second brake disc sample was produced. Observations during inertia dynamometer tests indicated a significant improvement in crack resistance for the new sample. Microstructural analyses confirmed that the implemented measures enhanced material homogeneity and largely eliminated nitrogen porosities. Consequently, the improved microstructure and increased crack resistance of the second sample were verified. This study highlights the critical impact of microstructural characteristics of brake discs on mechanical performance and demonstrates how microstructural improvements can enhance crack resistance. It underscores the importance of microstructural controls and process enhancements in increasing the reliability of brake discs.

 This study aims to comprehensively examine the microstructure of brake discs used in heavy-duty vehicles and its impact on crack resistance, with the goal of enhancing this resistance. In the initial phase, a brake disc sample exhibiting premature crack formation during inertia dynamometer testing was analyzed. Microstructural analysis revealed various defect modes such as non-homogeneous structure and nitrogen porosity within the material. These defect modes were found to adversely affect the crack resistance of the brake disc. To address these issues and improve the microstructural integrity of the material, a series of corrective measures were implemented. These included increasing the feeder inlet numbers during the casting process, optimizing the gating system design, and applying zirconium inoculation. Increasing feeder inlets and improving gating system design improved material flow, resulting in a more homogeneous structure, while zirconium inoculation helped reduce microstructural defects. Following these corrective actions, a second brake disc sample was produced. Observations during inertia dynamometer tests indicated a significant improvement in crack resistance for the new sample. Microstructural analyses confirmed that the implemented measures enhanced material homogeneity and largely eliminated nitrogen porosities. Consequently, the improved microstructure and increased crack resistance of the second sample were verified. This study highlights the critical impact of microstructural characteristics of brake discs on mechanical performance and demonstrates how microstructural improvements can enhance crack resistance. It underscores the importance of microstructural controls and process enhancements in increasing the reliability of brake discs.

 Bu çalışma, ağır hizmet araçlarında kullanılan fren disklerinin mikroyapısının, çatlak dayanımına olan etkisini detaylı bir şekilde incelemeyi ve bu dayanımı iyileştirmeyi hedeflemektedir. İlk aşamada, atalet dinamometresi testinde beklenenden daha erken çatlak oluşumu gösteren bir fren diski numunesi incelenmiştir. Mikroyapısal analiz sonucunda, malzeme içindeki homojen olmayan yapı ve azot boşlukları gibi çeşitli hata modları tespit edilmiştir. Bu hata modlarının fren diskinin çatlak dayanımını olumsuz yönde etkilediği görülmüştür. Hata modlarını gidermek ve malzemenin mikroyapısal bütünlüğünü artırmak amacıyla bir dizi iyileştirici önlem uygulanmıştır. Bunlar arasında, döküm işlemi sırasında besleyici giriş sayısının arttırılması, yolluk tasarımının iyileştirilmesi ve zirkonlu aşılama uygulamaları bulunmaktadır. Besleyici girişlerinin arttırılması ve yolluk tasarımının iyileştirilmesi, malzeme akışını iyileştirerek daha homojen bir yapının elde edilmesini sağlamış, zirkonlu aşılama uygulaması ise mikroyapısal kusurların azaltılmasına yardımcı olmuştur. Bu iyileştirici aksiyonlar sonrasında ikinci bir fren diski numunesi üretilmiştir. Yeni numunenin, atalet dinamometresi testlerinde, çatlak dayanımının belirgin bir şekilde arttığı gözlemlenmiştir. Yapılan mikroyapısal analizler, uygulanan önlemlerin malzeme içerisindeki homojenliği artırdığını ve azot boşluklarını büyük ölçüde giderdiğini göstermiştir. Sonuç olarak, ikinci numunenin mikroyapısının iyileştiği ve çatlak dayanımının arttığı doğrulanmıştır. Bu çalışma, fren disklerinin mikroyapısal özelliklerinin mekanik performans üzerindeki kritik etkisini vurgulamakta ve mikroyapısal iyileştirmelerin çatlak dayanımını nasıl artırabileceğini göstermektedir. Çalışmada, fren disklerinin güvenilirliğini artırmak için mikroyapısal kontrollerin ve üretim süreci iyileştirmelerinin önemi ortaya koyulmuştur.

Makale detayları

Microstructural Impact on Crack Resistance in Heavy-Duty Vehicle Brake Discs

Yazarlar:

Zehra Çınarcık | Bora Güntay

Yayıncı:

Gazi University

Ana Başlıklar:

Malzeme Tasarım ve Davranışları

Dergi:

Gazi Üniversitesi Fen Bilimleri Dergisi Part C: Tasarım ve Teknoloji Vol.12 Issue 4, pp.913-924

Belge Tipi:

Makale

Yayın Tarihi:

12/2024

Belge Dili:

Türkçe

Document ID (Org No.):

2001337746

pISSN:

2147-9526

heavy-duty vehicle brake disc

microstructural defects

nitrogen porosity

fatigue test

lamellar graphite cast iron

gray cast ironağır ticari araç fren diski

mikroyapı kusurları

azot boşluğu

yorulma testi

lamel grafitli dökme demir

gri dökme demir

Sayı

Makale detayları

Yazarlar: Zehra Çınarcık | Bora Güntay

Yayıncı: Gazi University

Ana Başlıklar: Malzeme Tasarım ve Davranışları

Dergi: Gazi Üniversitesi Fen Bilimleri Dergisi Part C: Tasarım ve Teknoloji Vol.12 Issue 4, pp.913-924

Belge Tipi: Makale

Yayın Tarihi: 12/2024

Belge Dili: Türkçe

Document ID (Org No.): 2001337746

pISSN: 2147-9526

Sayı

Yazarlar:

Zehra Çınarcık | Bora Güntay

Yayıncı:

Gazi University

Ana Başlıklar:

Malzeme Tasarım ve Davranışları

Dergi:

Gazi Üniversitesi Fen Bilimleri Dergisi Part C: Tasarım ve Teknoloji Vol.12 Issue 4, pp.913-924

Belge Tipi:

Makale

Yayın Tarihi:

12/2024

Belge Dili:

Türkçe

Document ID (Org No.):

2001337746

pISSN:

2147-9526