Analysis of fracture limit curves and void coalescence in high strength interstitial free steel sheets formed under different stress conditions

One kind of high strength interstitial free steel sheets are annealed in a salt bath at 810 C for different times (1-30 s). The microstructure and recrystallized texture evolution during annealing are investigated using the optical microscopy and the Electron Back Scattered Diffraction technique. The results show that beginning and finishing of recrystallization are observed in the sample annealed at 810 C for 8 and for 20 s, respectively. The recrystallized grains nucleate in the order of ‹111›//ND, ‹110›//ND and ‹100›//ND. Recrystallized grains with ‹111›//ND orientation nucleate firstly in the ‹111›//ND deformed grains as well as at their boundaries and grow up by consuming the ‹111›//ND deformed grains at the initial stage of recrystallization. The ‹111›//ND recrystallized grains grow up by depleting the remained formed ‹100›//ND grains after the full consumption of the ‹111›//ND deformed grains. The overall recrystallization texture is mainly the ‹111›//ND component in the steel.

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Effects of Finish Rolling Temperature on Microstructure and Mechanical Properties of Ferritic-Rolled P-Added High Strength Interstitial-Free Steel Sheets

Journal of Iron and Steel Research International ◽

10.1016/s1006-706x(11)60063-0 ◽

2011 ◽

Vol 18 (5) ◽

pp. 42-46 ◽

Cited By ~ 8

Author(s):

Wei-min Guo ◽

Zuo-cheng Wang ◽

Sheng Liu ◽

Xie-bin Wang

Keyword(s):

Mechanical Properties ◽

High Strength ◽

Rolling Temperature ◽

Interstitial Free ◽

Finish Rolling Temperature ◽

Steel Sheets ◽

Microstructure And Mechanical Properties ◽

Finish Rolling ◽

Interstitial Free Steel

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Experimental investigation on resistance spot welding of dissimilar weld joints

Proceedings of the Institution of Mechanical Engineers Part E Journal of Process Mechanical Engineering ◽

10.1177/0954408920968351 ◽

2020 ◽

pp. 095440892096835

Author(s):

Rohit Verma ◽

Kanwer Singh Arora ◽

Lochan Sharma ◽

Rahul Chhibber

Keyword(s):

Welding Process ◽

High Strength ◽

Dynamic Resistance ◽

Interstitial Free ◽

Resistance Spot ◽

Dissimilar Weld ◽

Steel Sheets ◽

Weld Joints ◽

Resistance Spot Weld ◽

Weld Current

In the present study, galvanized High Strength Interstitial Free (HIF) steel sheets, and Dual Phase (DP780) steel sheets were used for the investigations. Resistance spot weld joints were fabricated between dissimilar steel sheets. The variation in dynamic resistance (DR) with the change in welding process parameters such as weld current, weld time and electrode force were used for establishing the range of adequate weld nugget formation parameters. Effect of these parameters over tensile strength, nugget diameter and the observed failure mode was studied using one factor at a time (OFAT) approach. Microstructure and hardness of parent metal, fusion & HAZ region has also been studied.

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