功能型先進超高強度汽車用鋼開發

Development of Advanced Ultra-High Strength Steels with Excellent Functions for Automotive Application

楊國政(K.C. Yang) ； 涂睿帆(J.F. Tu) ； 王泰翔(T.H. Wang) ； 王琮賢(T.H. Wang) ； 田宗凱(T.K. Tien)

《鑛冶：中國鑛冶工程學會會刊》 64卷4期 (2020/12) Pp. 56-70

https://doi.org/10.30069/MM.202012_64(4).06

摘要

雙相鋼因具高強度與高延性，為最廣泛使用的先進高強度鋼（AHSS），但隨著溫室氣體減排及碰撞安全的要求日趨嚴苛，汽車為能大幅減重而大量使用強度高於980MPa的超高強度鋼（UHSS）。但提高到980MPa等級，雙相鋼的擴孔性明顯下降，強度即難以再往上提升，且延性明顯不足，導致無法進行嚴苛的冷加工成形，因此唯有發展出兼具高擴孔性，或兼具高剛性，或兼具高吸能（高強塑積）的超高強度鋼，方能克服雙相鋼在汽車部件應用上的限制，此系列鋼材即稱之為功能型先進超高強度汽車用鋼。本研究透過變韌鐵相變化控制技術、自回火麻田散鐵控制技術、沃斯田鐵逆變態（Austenite Reverted Transformation，ART）控制技術等三項創新技術的發展，分別開發出高剛性JSC1180Y、高擴孔性JSC980YH、高延性CSC980TL等三項功能型系列產品，填補國內汽車產業鏈供應缺口，提升我國汽車工業發展的質與量，為車體減重及節能減碳貢獻心力。

關鍵字

先進高強度鋼 ； 功能型汽車用鋼 ； 高延性 ； 高擴孔

並列摘要

The dual-phase (DP) steel, featuring combination of high strength and excellent ductility, is the most popular advanced high-strength steels. In order to meet the tightening regulations of green gas emission and collision safety, steels with strength exceeding 980MPa (UHSS, ultra-high strength steel) are desperately needed. However, the hole expansion ratio and ductility of UHSS auto parts are often deficient when subject to complex cold working. Therefore, development of advanced UHSS with high hole expansion ratio, high rigidity (yield strength), or high energy absorption (strength-ductility product) is in need. In this study, the ferrite + martensite dual phase microstructures are modified to form fully bainite, auto-tempered martensite, and austenite reverted transformation (ART) which give rise to steel grades of JSC980YH (high hole expansion ratio), JSC1180Y (high rigidity), and CSC 980TL (high energy absorption), respectively. The newly developed UHSSs not only fulfill the market demands of domestic automotive industry but also reduce vehicle weight and contribute to energy saving and CO_2 emission reduction.

並列關鍵字

AHSS ； complex cold workability ； high elongation ； high hole-expansibility