Table of Contents

    • 98

    • Quantitative Methods for Evaluation of Centerline Segregation

      Centerline segregation in continuous casting is a well-known issue that is becoming increasingly critical as more highly alloyed steel grades are being developed and produced. This paper summarizes methods for evaluation of centerline segregation and discusses their advantages and disadvantages. A method that is relatively simple, requires minimal time and effort, and has low capital costs is desired for assessing centerline segregation in as-cast products. The prospects for development of such a method will be discussed.

    • 110

    • Microscale Image-Based Finite Element Modeling of High-Speed Steel Microstructure

      Spun cast bi-metallic rolls used in the early finishing stands of the hot strip mill are comprised of a highly alloyed working shell layer and ductile iron core. The campaign length, strip surface quality and mill performance depend on the characteristics of the high-speed steel shell microstructure. In order to assess the local shell microstructural response, microscale image-based finite element models were developed. Preliminary results were compared to actual observations.

    • 118

    • Control of AHSS Coil Cooling After Hot Rolling to Improve Downstream Processin

      Hot strip rolling of advanced high-strength steel for automotive applications is often followed by adverse phenomena that hamper downstream processing, deteriorate quality and yield of final products, and increase production costs. Special measures should be taken to control cooling of hot band coils after hot rolling. Finishing hot rolling parameters could be also adjusted to further control microstructure evolution after rolling.

    • 124

    • Process Influences on Press-Hardened Steel Microstructure and Impact Performance

      It has been shown that steel chemistry and austenitization practices significantly influence the impact performance of the resultant martensite in press-hardened steel as measured by laboratory-scale methods and component-level validation. These results emphasize the necessity of proper process monitoring and quality procedures to ensure product integrity.

    • 134

    • Mechanism for Carbon Transfer From Magnesia-Graphite Ladle Refractories to Ultralow-Carbon Steel

      Mechanisms of carbon transport between magnesia-graphite ladle refractories and ultralow-carbon steel were investigated using laboratory dip tests with commercial ladle refractories in a vacuum induction furnace. The reacted refractories were examined by scanning electron microscopy and energy-dispersive x-ray spectroscopy analysis to observe changes in the refractory that influenced the rate of carbon pickup to the steel.

    • 144

    • Plastic Deformation Behavior of Weld Lines in ERW Steel Pipe

      The strain fields of plastically deformed steel pipe samples, one seamless, one electrical resistance welded (ERW) steel pipe with a good weld line, and one ERW with a defective weld line, were analyzed using two-dimensional digital image correlation. It is proposed that the ERW weld line can be treated in general as a notch, using the three-point flattening test of a perfect pipe section as the standard. More details in mapped strain field, implication of current work to ERW steel pipe quality evaluation, and flattening test will also be discussed.