熱衝壓異厚拼焊板B柱之製程開發

為因應車身輕量化與高安全性的需求，本研究旨在開發應用於汽車B柱之熱衝壓異厚拼焊板（TWB）製程。研究採1.8 mm與1.2 mm硼鋼板進行雷射拼焊與試作，先以CAE分析確保成形性，再透過實體試模探討不同持壓時間（5~20秒）對尺寸精度與機械性能的影響。結果顯示，增加持壓時間能有效提升尺寸精度；三點彎曲試驗中，異厚件相較於等厚件（最大反力23 kN vs. 30 kN），展現更佳的韌性與吸能效果，成功達成局部弱化之設計目標。本研究驗證了此先進製程的可行性，並為後續優化提供關鍵數據。

To meet the demands for vehicle lightweighting and high safety, this article aims to develop a hot stamping process for Tailor Welded Blanks (TWB) applied to an automotive B-pillar. The study utilizes 1.8 mm and 1.2 mm boron steel sheets for laser welding and trial production. Formability is first ensured through CAE analysis, followed by physical trials to investigate the effects of different holding times (5-20 seconds) on dimensional accuracy and mechanical properties. The results indicate that a longer holding time effectively enhances dimensional accuracy. In the three-point bending test, the TWB part demonstrates superior toughness and energy absorption (maximum reaction force of 23 kN vs. 30 kN for the uniform thickness part), successfully achieving the design objective of localized weakening. This research validates the feasibility of this advanced process and provides crucial data for future optimization.