Direnç Nokta Kaynağı ile Birleştirilmiş AlSi Kaplamalı SABC1470 Çeliklerinde Patchwork Uygulamasının Mikroyapısal ve Mekanik Olarak İncelenmesi

Abstract

Bu çalışma, AlSi kaplamalı SABC1470 çeliği kullanılarak direnç nokta kaynağı ile yapılan patchwork üretim yönteminin, sıcak şekillendirme prosesi öncesi ve sonrasında mikroyapısal ve mekanik davranışlarının, kaynaklanabilirlik fizibilitesi üzerindeki etkilerini analiz etmeyi amaçlamaktadır. Deneysel çalışmalar kapsamında, aynı kalınlığa ve malzeme özelliğine sahip iki sac plaka, direnç nokta kaynak yöntemi ile birleştirilmiş ve farklı kaynak parametrelerinin kaynak çekirdek çapına ve mikroyapıya etkisi detaylı olarak incelenmiştir. Spot kaynağı sonrası uygulanan presle bükme işlemi ile radius bölgelerinde meydana gelen yapısal değişimler taramalı elektron mikroskobu (SEM) yardımıyla analiz edilmiştir. Özellikle çekirdek çapının standartlara uygunluğu değerlendirilmiş; sıcak şekillendirme prosesi sonrasında spot çekirdeğinde meydana gelen kayma ve çatlak oluşumları ile ilişkisi ortaya konmuştur. Bu bulgular, direnç nokta kaynağı ile yapılan patchwork uygulamalarında kaynak kalitesinin ve mikroyapısal bütünlüğün üretim sonrası şekillendirme davranışı üzerindeki belirleyici etkisini göstermektedir.

Keywords

• Patchwork Yöntemi
• Direnç Nokta Kaynağı
• Sıcak Şekillendirme
• SABC1470
• Mikroyapı Analizi
• AlSi Kaplama

Microstructural and Mechanical Investigation of Patchwork Application in AlSi Coated SABC1470 Steels Joined by Resistance Spot Welding (RSW)

Abstract

This study aims to evaluate the influence of the patchwork manufacturing method, conducted by resistance spot welding on AlSi-coated SABC1470 steel, on the microstructural and mechanical behaviors before and after the hot stamping process, with a focus on weldability feasibility. In the experimental phase, two sheet metals with identical thickness and material properties were joined by resistance spot welding and the influence of different welding parameters on nugget diameter and microstructure was examined in detail. Post-weld bend tests were conducted using a press, and structural transformations occurring in the radius regions were analyzed with a scanning electron microscope (SEM). Particular attention was given to assessing the compliance of the nugget diameter with established standards, and its correlation with slippage and crack formation observed after the hot stamping process was elucidated. The findings demonstrate that weld quality and microstructural integrity in patchwork applications significantly affect the post-forming behavior of components produced by resistance spot welding.

Keywords

• Patchwork Technique
• Resistance Spot Welding
• Hot Stamping
• SABC1470
• Microstructure Analysis
• AlSi Coating

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