会议论文详细信息
International Deep Drawing Research Group 37th Annual Conference
Importance of hole punching conditions during Hole Expansion test
Goncalves, J.^1
Global RandD ArcelorMittal Maizieres, Voie Romaine, BP30320, Maizieres-les-Metz-Cedex
57283, France^1
关键词: Advanced high strength steel;    Car body manufacturing;    Hole-expansion ratios;    Sources of variability;    Speed difference;    Steel microstructure;    Technical specifications;    Termination points;   
Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/418/1/012060/pdf
DOI  :  10.1088/1757-899X/418/1/012060
来源: IOP
PDF
【 摘 要 】

There is an increasing interest in the steelmaking and automotive industries to evaluate the edge cracking sensitivity of Advanced High Strength Steel sheets used in car body manufacturing. Currently, the Hole Expansion test is the only test procedure that is defined by norms (JFS and ISO). This test is increasingly used to assess the formability of cut-edges on punched sheets because it is relatively simple. However, it has been already shown that there can be large differences in Hole Expansion Ratio (HER) values generated by different testing facilities. Among the main sources of variability: punched hole quality and hole expansion termination point. Hole punching operation has a detrimental effect on cut-edge quality and HER values. However, current standards do not give any recommendation. No technical specification is given for the tooling, quality control system and punching speed. It has been stated that the press speed difference in the hole punching operation are significantly different from one laboratory to another one and some steel microstructures sensitive to it. However, very few papers and data are available. As a result, an experimental study was conducted to examine this important issue. A specific 4-post assembly tool was designed to guarantee the best punched hole quality. Different punching speeds, from 0.2mm/s to 367mm/s were tested on different steel sheets (mild steel, AHSS including TWIP and 3rd Gen steel) to emphasize or not the influence on final HER values.

【 预 览 】
附件列表
Files Size Format View
Importance of hole punching conditions during Hole Expansion test 1023KB PDF download
  文献评价指标  
  下载次数:7次 浏览次数:12次