Effect of Hot Rolling on Bonding Characteristics and Impact Behavior of a Laminated Composite Material Based on UHCS-1.3
- PDF / 530,383 Bytes
- 6 Pages / 593.972 x 792 pts Page_size
- 35 Downloads / 163 Views
ure of laminated composite materials by rolling processes is more efficient and economical than other processes such as hot press or adhesive bonding. Hot roll bonding consists of diffusion bonding in the solid state of several metal sheets under heat and pressure either sequentially or simultaneously.[1,2] Thermomechanical parameters such as temperature, time, and pass reduction are essential to refine the microstructure[3,4] and control the quality of the bond.[5] The roll bonding technique has made numerous progress in solid-state processing, for instance, by accumulative roll bonding, which is generally recognized as an effective processing approach for producing nanoscale structures in bulk materials. However, due to the severe deformation conditions imposed, the control of the interface bond is difficult. In this article, different hot rolling processing conditions across the A1 temperature have been used to study the bonding behavior in a laminate consisting of ultrahigh carbon steel (UHCS) and mild steel (MS). The A1 temperatures of the MS and the UHCS are 720 C and 734 C, respectively. Previous studies have manifested that multilayer composites constituted by UHCS have improved the mechanical behavior of their constituent materials, especially of the less tough M. POZUELO, Postdoctoral Researcher, is with the Department of Materials Science and Engineering, University of California, Los Angeles, CA 90095-1595. Contact e-mail: [email protected] F. CARREN˜O, Staff Researcher, C.M. CEPEDA-JIME´NEZ, Postdoctoral Researcher, and O.A. RUANO, Professor, are with the Departamento de Metalurgia Fı´ sica, CENIM, CSIC, 28040 Madrid, Spain. Manuscript submitted July 27, 2007. Article published online February 5, 2008 666—VOLUME 39A, MARCH 2008
UHCS.[1,5–13] The excellent mechanical properties of these laminated composite materials are the result of controlling the bond processing conditions. For this purpose, a study of the influence of thermomechanical factors, in particular, the path of thickness reduction, on the interface bonding has been carried out.
II.
MATERIAL AND EXPERIMENTAL PROCEDURE
A laminated composite material consisting of alternatively five layers of UHCS containing 1.35 pct C (UHCS-1.35C) and five layers of mild steel (MS-0.091C) was chosen for this study. The compositions (mass pct) of the UHCS and MS are 1.35 pct C-0.54 pct Cr-0.25 pct Mn-0.17 pct Si and 0.091 pct C-0.019 pct Cr-0.35 pct Mn-0.019 pct Si, respectively. Squares of dimensions 60 · 60 · 4 mm3 and 60 · 60 · 3.5 mm3 for the UHCS and MS, respectively, were cut and surface ground to quality ISA H7 to remove oxides and then cleaned in acetone. Finally, these steel layers were alternatively piled up to obtain a sandwich of a total thickness of 28.7 mm with a volume fraction of UHCS of around 60 pct. This sandwich was hermetically welded at the edges by tungsten inert gas to avoid oxygen penetration and delamination during processing. A twin rolling mill of 134-mm roll diameter at a rolling speed of 366 mm/s was used for high-temperature rolling
Data Loading...
