SCIENCE AND TECHNOLOGY OF CASTING PROCESSES_1 ppt

SCIENCE AND TECHNOLOGY OF CASTING PROCESSES Edited by Malur Srinivasan Science and Technology of Casting Processes http://dx.doi.org/10.5772/3128 Edited by Malur Srinivasan Contributors Limei Tian, Zhaoguo Bu, Zhihua Gao, Na Li, Edgardo Roque Benavidez, Sebastian Friedhelm Fischer, Andreas Bührig- Polaczek, Ioan Ruja, Constantin Marta, Doina Frunzaverde, Monica Rosu, Ram Prasad, Malur Narayanaswamy Srinivasan, Subramanyam Seetharamu, Tasaki, Qing Liu, Xiaofeng Zhang, Shinichiro Komatsu, Ramaprasad ( M.S.Ramaprasad) Meenasamudram Seshadri Published by InTech Janeza Trdine 9, 51000 Rijeka, Croatia Copyright © 2012 InTech All chapters are Open Access distributed under the Creative Commons Attribution 3.0 license, which allows users to download, copy and build upon published articles even for commercial purposes, as long as the author and publisher are properly credited, which ensures maximum dissemination and a wider impact of our publications. After this work has been published by InTech, authors have the right to republish it, in whole or part, in any publication of which they are the author, and to make other personal use of the work. Any republication, referencing or personal use of the work must explicitly identify the original source. Notice Statements and opinions expressed in the chapters are these of the individual contributors and not necessarily those of the editors or publisher. No responsibility is accepted for the accuracy of information contained in the published chapters. The publisher assumes no responsibility for any damage or injury to persons or property arising out of the use of any materials, instructions, methods or ideas contained in the book. Publishing Process Manager Iva Lipovic Technical Editor InTech DTP team Cover InTech Design team First published October, 2012 Printed in Croatia A free online edition of this book is available at www.intechopen.com Additional hard copies can be obtained from orders@intechopen.com Science and Technology of Casting Processes, Edited by Malur Srinivasan p. cm. ISBN 978-953-51-0774-3 free online editions of InTech Books and Journals can be found at www.intechopen.com Contents Preface VII Section 1 Disposable Mold Castings 1 Chapter 1 Sand Mold Press Casting with Metal Pressure Control System 3 Ryosuke Tasaki, Yoshiyuki Noda, Kunihiro Hashimoto and Kazuhiko Terashima Chapter 2 Progress in Investment Castings 25 Ram Prasad Chapter 3 New Casting Method of Bionic Non-Smooth Surface on the Complex Casts 73 Tian Limei, Bu Zhaoguo and Gao Zhihua Chapter 4 Evaluation and Modification of the Block Mould Casting Process Enabling the Flexible Production of Small Batches of Complex Castings 87 Sebastian F. Fischer and Andreas Bührig-Polaczek Section 2 Reusable Mold Castings 115 Chapter 5 Permanent Molding of Cast Irons – Present Status and Scope 117 M. S. Ramaprasad and Malur N. Srinivasan Chapter 6 Control Technology of Solidification and Cooling in the Process of Continuous Casting of Steel 169 Qing Liu, Xiaofeng Zhang, Bin Wang and Bao Wang Chapter 7 Mould Fluxes in the Steel Continuous Casting Process 205 Elena Brandaleze, Gustavo Di Gresia, Leandro Santini, Alejandro Martín and Edgardo Benavidez Section 3 Evaluation of Castings 235 Chapter 8 Segregation of P in Sub-Rapid Solidified Steels 237 Na Li, Shuang Zhang, Jun Qiao, Lulu Zhai, Qian Xu, Junwei Zhang, Shengli Li, Zhenyu Liu, Xianghua Liu and Guodong Wang Chapter 9 Accuracy Improving Methods in Estimation of Graphite Nodularity of Ductile Cast Iron by Measurement of Ultrasonic Velocity 265 Minoru Hatate, Tohru Nobuki and Shinichiro Komatsu Chapter 10 Fracture Toughness of Metal Castings 285 M. Srinivasan and S. Seetharamu Chapter 11 Research on Simulation and Casting of Mechanical Parts Made of Wear-and-Tear-Resistant Steels 313 Ioan Ruja, Constantin Marta, Doina Frunzăverde and Monica Roşu ContentsVI Preface Casting process is the most direct method of producing a product from the chosen material. Though products in all the three major classes of materials, metals, ceramics and polymers can be produced by this method, casting of metals is by far the most widely used process. The basic steps in the casting process are preparation of the material in the liquid state, transferring the liquid material into a shaping mold, allowing the transformation of liquid material in the mold into a solid form. The solid object can then be used directly in applications or subjected to secondary operations like thermal treatment involving solid state transformations or material removal. In one important case (continuous casting), the solid is subjected to significant plastic deformation to get the final shape of the object. In recent times, innovations have been developed to process some metallic materials in a semi- solid form, giving rise to interesting behavior of the castings. As with any other process, the factors affecting the casting process are the quality, the cost and the environmental effects. The choice of a given casting process will have to be made consistent with acceptable levels of the degree of combination of these factors. Several alternatives may be available to make a cast product, as for example, a sand casting or a permanent mold casting, as the latter may have a lesser environmental impact. The decision may not be a straightforward one, as factors such as molten metal temperature and casting size may favor the sand casting process. On the other hand, the product quality of a permanent mold casting may be better than that of a sand casting. It follows therefore that a careful analysis of the science and technology of each process is extremely important. In view of the complexity of each, it is advisable to undertake separate studies of each and later, based on a suitable combination, choose a process that leads best towards the goal of high quality, low cost and low environmental impact. The science of metal casting mainly deals with control of fluid mechanics and heat transfer at the macro-level and the additional control of mass transfer both at the micro-level and macro-level. All the three factors are interwoven but each is capable of independent analysis before integration with others. Also, to conform to the designer's requirements, an engineered casting must possess acceptable level of properties, the mechanical properties often being most important. Solid mechanics mainly governs the mechanical behavior of castings. The technology used deals with both cost and environmental aspects, consistent with the proper application of the scientific factors. Needless to say, the goal of attaining high quality, low cost and low environmental impact in a casting process is not easy and requires extensive research and understanding in each area. Obviously, proper evaluation procedures must be established to assess the quality, reliability and serviceability of the castings. This book is a collection of chapters contributed by experts in their fields. The effect of environmental impact is recognized in two chapters but in view of the growing global concerns, it is desirable to have more extensive documentation of this factor and its interaction with the science and processing of castings. Prof. Malur Srinivasan Professor of Mechanical Lamar University Texas, USA. PrefaceVIII Section 1 Disposable Mold Castings [...]... considered 13 Science and Technology of Casting Processes To observe the penetration growth under the force of gravity, a test experiment has been achieved with molten metal A suggested casting mould shape and the casting are shown in Fig 10 The molten metal was poured into the casting mould quickly at 1,400 ℃, and kept at 1673[K] until the end of filling The casting mould is 1,000 mm in height and Φ45 mm... Modeling and feedforward flow rate control of au‐ tomatic pouring system with real ladle Journal of Robotics and Mechatronics, 19(2), 205-211 23 24 Science and Technology of Casting Processes [4] Noda, Y., Yamamoto, K., & Terashima, K (2008) Pouring control with prediction of filling weight in tilting-ladle-type automatic pouring system International Journal of Cast Metals Research, Science and Engineering... Figure 17 Observational experiment of unstationary flow 19 20 Science and Technology of Casting Processes 8.1 Pressure Model of Unstationary Flow Fig 18 shows the rising flow during pressing and each stream line of molten metal’s flow The unstationary Bernoulli equation for two points: S and B on a given stream line in the flow of an incompressible fluid in the presence of gravity is S ∫ ∂∂U ds + 1 U t... into narrow pass d(eh)[m] such that stage-3 in Fig 3 As seen from Eq 1, the effect of λ on the variation of pressure ˙ Pb(t) becomes larger with the increase of liquid level eh[m] and flow velocity e h [m/s] Thus, 7 8 Science and Technology of Casting Processes ˙ exact value of λ(T) must be given for the region of eh and e h , because our purpose is to sup‐ press the maximum pressure value Therefore... experiments will be done 11 12 Science and Technology of Casting Processes 7 Experimental confirmation of physical metal penetration generation In this section, we tried several molten metal experiments to clarify the mechanism of physi‐ cal metal penetration growth and the boundary condition of physical metal penetration gen‐ eration, and to validate the control performance of the feedforward method using... the head and hydrodynamic pressure determined by using Bernoulli’s theorem, and the pres‐ sure loss by viscosity flow friction is represented by the following equation: 5 6 Science and Technology of Casting Processes ( ) l(eh ) ρ ˙ Pb(t) = ρgeh (t) + 2 1 + λ(T ) d(e ) e h (t)2 h (1) Figure 3 Mold shape and flow pass change where ρ[kg/m3] is the density of fluid and g[m/s2] is the acceleration of gravity... Engineering of Cast Metals, Solidification and Casting Processes, AFC-10 Special, 21(1-4), 287-292 [5] Hu, J V J H (1994) Dynamic modeling and control of packing pressure in injection molding Journal of Engineering Materials and Technology, 116(2), 244-249 [6] Tasaki, R., Noda, Y., & Terashima, K (2008) Sequence control of pressing velocity for pressure in press casting process using greensand mould... creation and control of sand mold press cast‐ ing "post-filled formed casting process Foundry Trade Journal International (The Jour‐ nal of The Institute of Cast Metals Engineers), 183(3670), 314-318 [2] Terashima, K., Noda, Y., Kaneto, K., Ota, K., Hashimoto, K., Iwasaki, J., Hagata, Y., Suzuki, M., & Suzuki, Y (2009) Novel creation and control of san mold press casting “post-filled formed casting. .. process 8 Modelling and Control Unstationary Flow The online estimation of pressure inside the mold is necessary in the press casting system The CFD analysis, based on the exact model of a Navier-Stokes equation, is very effective for analyzing fluid behavior offline and is useful for predicting the behavior and optimizing of a casting plan [8-9] However, it is not sufficient for the design of a pressing... axis, and the cut specimens at each depth, Hl, are pictured respectively The penetration growths in the early phase and the final phase of solidification are con‐ firmed clearly from Figs 11(a) and (b) In Fig 11(a) (Hl =150 (mm)), early phase of penetra‐ Sand Mold Press Casting with Metal Pressure Control System http://dx.doi.org/10.5772/51082 tion in casting surface is identified, and some small sand . SCIENCE AND TECHNOLOGY OF CASTING PROCESSES Edited by Malur Srinivasan Science and Technology of Casting Processes http://dx.doi.org /10 .5772/ 312 8 Edited by Malur Srinivasan Contributors Limei. Scope 11 7 M. S. Ramaprasad and Malur N. Srinivasan Chapter 6 Control Technology of Solidification and Cooling in the Process of Continuous Casting of Steel 16 9 Qing Liu, Xiaofeng Zhang, Bin Wang and. Komatsu Chapter 10 Fracture Toughness of Metal Castings 285 M. Srinivasan and S. Seetharamu Chapter 11 Research on Simulation and Casting of Mechanical Parts Made of Wear -and- Tear-Resistant Steels 313 Ioan