Session Sheet - 13th International Conference on the Technology of Plasticity (ICTP 2021): Novel Processes II

13th International Conference on the Technology of Plasticity (ICTP 2021): Novel Processes II
Program Organizers: Glenn Daehn, Ohio State University; Libby Culley, The Ohio State University; Anupam Vivek, Ohio State University; Jian Cao, Northwestern University; Brad Kinsey, University of New Hampshire; Erman Tekkaya, TU Dortmund; Yoshinori Yoshida, Gifu University

Friday 10:20 AM
July 30, 2021
Room: Virtual: Room A
Location: Virtual

Session Chair: Taeseon Lee, Incheon National University

Vacuum Hot-roll Bonding of Titanium and Carbon Steel Using Pure Iron Interlayer: Chao Yu¹; Xiao Liu¹; Hong Xiao¹; Yunpeng Zhao¹; ¹Yanshan University
    In this paper, the effect of a pure iron interlayer on properties of the multi-pass hot-roll bonding titanium/carbon steel plate was studied. The mechanical and microstructural properties of the composite plate were investigated by optical microscopy and scanning electron microscopy, as well as tensile-shear, bending and tensile tests. The results show that when the reduction ratio is below 18%, the shear strength of the interface is higher with the pure iron interlayer than without it. At 35% reduction, the shear strength is similar in both cases. At a reduction ratio of 68%, with the pure iron interlayer, fracture of the bonding interface occurs on the titanium matrix, whereas without the pure iron interlayer, fracture occurs on both the titanium matrix and the compound layer on the interface. Including the pure iron interlayer improves the bending and tensile properties of the titanium/carbon steel plate appreciably.

Accurate Mapping of Thermal Camera Measurements on Planar Deformations: Celalettin Karadogan¹; Mathias Liewald¹; ¹Institute for Metal Forming Technology - University of Stuttgart
    Synchronous measurement of temperature distribution with infrared cameras has been increasingly used in the thermomechanical analysis of sheet material behavior. Measured temperatures are used, however, only qualitatively due to absence of well-developed coordinate mapping methods applicable to thermographic measurements. The study introduces a primitive, easy to use, yet effective approach for accurate coordinate mapping from real to image coordinates, and inverse, applicable to even highly oblique thermographic and photographic measurements of planar deformations. The method is not limited to any camera model and precisely counteracts inhomogeneous image distortion. It can be used as a stand-alone optical measurement approach, but at the same time, it allows flawless correlation with commercial DIC systems by allowing accurate mapping between thermographic and photographic measurements of planar deformation in real and image coordinates.

Influence of Axial Feed-rate on Shape and Thickness Changes during Multi-pass Tube Spinning: Experiments and Modelling: Biplov Roy¹; Yannis P. Korkolis²; Yoshio Arai¹; Wakako Araki¹; Takafumi Iijima³; Jin Kouyama³; ¹Saitama University; ²The Ohio State University; ³Asahi Seisakusho Co., Ltd.,
    The primary purpose of this research is to investigate the influence of axial feed-rate on shape and thickness changes in multi-pass, mandrel-free tube spinning for producing a hemispherical shape at room temperature. The target shape is formed experimentally by 7 spinning passes from annealed, pure aluminum AA1070-O tube. The experiments are conducted with three different axial feed-rates i.e. 2, 5 and 7.5 mm/rev., and interrupted after spinning passes 2, 4 and 7. In every experiment, the tube buckled at some point during the process, due to the high axial-feed. It was also found that decreasing the axial feed-rate generates higher elongation and lower thickness change. A 3D elastic-plastic finite element (FE) model of the multi-pass tube spinning process is described. The mechanisms of influence of the axial feed-rate on axial buckling, tube elongation and thickness change are discussed through the comparison between experimental and simulation results.

A Brief Review on Theoretical Aspects of Bar Straightening with Recent Developments in its Modelling, Simulation, Control System and Stabilisation: Sanjib Roy¹; Arun Pal¹; Nripendra Das Talukder²; ¹Jadavpur University; ²Former Professor Emeritus
    This paper presents a brief review of various researches done on bar straightening. Bar straightening can be considered as a significant process in the value stream of bar production. The paper dealt briefly on various types of arrangements available in bar straightening process. The theoretical perspectives have been looked into in simplified manner. Residual stresses, curvature and bending moment thereof due to reverse kinematic bending have been discussed. A system approach has been taken as how development on bar straightening process emerged over the years. The recent developments in bar straightening using modelling / numerical modelling give an insight of reduction in curvature after reverse bending. Simulation / Numerical simulation approaches in bar straightening process have been looked into. Key aspects like positioning of rolls and minimisation of straightness errors have been considered. How control system is applied with Multi-Step Straightening Control System (MSSC) in reducing curvature has been discussed. The paper has been intended to present an overall view of bar straightening from inception till modern times.

Investigation on the Whole Forming Process of Super-large Flat Ring: Dan Xie¹; Wujiao Xu¹; Yu Wang¹; Rui Chen¹; ¹Chongqing University
    The main concerns of forming super-large rectangular ring are forming accuracy, rolling stability, uniformity of deformation and accordingly the distributed microstructure and related mechanical property of the rolled ring. In this paper, a rectangular ring with diameter of 9m is taken as an example, which is the bearing ring of a carrier rocket. To meet the requirements of formation and performance, the whole forming process, including multi-directional forging, punching, reaming and ring rolling is investigated step by step. Three multi-directional forging schemes are compared in order to improve the internal quality of ring billet. For the reaming process, four different reduction amounts per pass are designed to control the end surface quality of the reaming operation part. To refine grain and minimize the anisotropy of the rolled ring, the ring rolling process is divided into high temperature rolling and low temperature rolling, the feeding strategy of which are studied respectively.

Effect of Bending Intensity on Straightness in Spinner Straightener: Keiichiro Kawasaki¹; Takashi Kuboki¹; Shohei Kajikawa¹; Hiromichi Matumura²; Tetushi Ono²; Hikaru Seimiya²; ¹University of Electro-Communications; ²Shimomura Tokushu Seiko
    This paper presents the optimum processing condition of spinner straightener. Spinner straightener straightens wire rod using several straightening tools by subjecting the rod to repetitive bending and unbending with rotational movement. This research investigated the effect of bending intensity on straightness of wire by changing the die positions which determine the bending intensity. Both the experiment and an analysis were carried out for the investigation. One of the unique points of this study is the usage of actual operation line for the experiment instead of laboratory equipment. Another unique point is the combination of the finite element analysis (FEA) and a purpose built fundamental analysis. The analysis and experiment were in good agreement, and showed the existence of the optimum condition. The straightness was improved with the increase of the bending intensity up to the optimum bending intensity. However, excessive bending intensity deteriorated the straightness.