Incremental Sheet Forming Technologies

Principles, Merits, Limitations, and Applications

Ajay, Ravi Kant Mittal

• Publisher: CRC Press
• Year: 2020
• Print ISBN:
  9780367276744
• eBook ISBN:
  9781000179866
• Topic: Technology & Engineering
• Subtopic: Mechanics
• Index: Technology & Engineering

Incremental Sheet Forming (ISF) exempts use of dies and reduces cost for manufacturing complex parts. Sheet metal forming is used for producing high-quality components in automotive, aerospace, and medical industries. This book covers the benefits of this new technology, including the process parameters along with various techniques.

Each variant of this novel process is discussed along with the requirements of machinery and hardware. In addition, appropriate guidelines are also suggested regarding the relationship between process parameters and aspects of ISF process in order to ensure the applicability of the process on the industrial scale.

This book will be a useful asset for researchers, engineers in manufacturing industries, and postgraduate level courses.

1 Introduction and Need for Advanced Sheet Forming Techniques

1.1 Introduction

Since the advent of the human race many processes, tools and machines have evolved to manufacture products to make life easier and more enjoyable. In the twentieth century, many evolutions have taken place in an effort to meet the manufacturing challenges created by newer requirements, materials, tools and cost constraints, and the quest continues. The developments and advancements in the aero-space, automobile, marine, medical and many other sectors often require make-to-order manufacturing, and newer technology is required to meet this challenge. Such manufacturing systems need autonomous, flexibly integrated and adaptable processes that can respond quickly to dynamic requirements with real-time shop floor control of the process. Incremental sheet forming is an evolving modern manufacturing process for these situations, one of the buzz areas of research in sheet material manufacturing, for the economic manufacturing of custom objects. Manufacturing is a complex activity of converting raw materials into finished products with desired properties, shape and size, using a wide variety of processes, machinery, tools and other equipment with or without automation, the use of computers, robots, sensors and other special equipment; it requires people with diverse skills, knowledge and expertise in different disciplines. The effectiveness and efficiency of a manufacturing method depend on the flexibility and agility of the process as well as its feasibility for a particular application.

To carry out a manufacturing activity we require five Ms, viz. Men, Materials, Machines, Money and Methods. Methods refer to manufacturing methods used for making the desired products economically and quickly, with anticipated quality and adaptability to ever-changing needs and technological developments. In addition, knowledge of the various materials, tools, machine tools, accessories, manufacturing processes, metrology and testing instruments for checking materials or products is essential for understanding manufacturing processes.

1.2 Manufacturing Processes

The manufacturing processes or techniques for producing desired products or components are conventionally grouped into five basic production processes based on the handling of the material required to convert it into a component by giving it the desired shape, size, accuracy, finish and properties. These are:

• Casting processes
• Material removal processes
• Forming/deformation processes
• Joining processes
• Special processes

The basics of these processes are briefly described here to refresh the concepts of the different methods of manufacturing, the machines and tools required for each of them and the terminologies involved.

1.2.1 Casting Processes

Casting is one of the oldest known methods for shaping materials. In casting processes, the material is melted and liquid material is poured into a cavity (called a mold) of the shape and size of the required product where it is allowed to solidify. After solidification, the product, called “castings”, is extracted from the mold. Casting processes are widely used to produce products of small sizes to very large sizes, with very intricate shapes and with strength and rigidity frequently not obtainable by other manufacturing processes.

The casting process has low production costs but is a labor-intensive process, requiring other operations to get the finished product, with limitations of dimensional accuracy and surface finish. Special casting processes, like the die-casting process, investment casting process, vacuum-sealed molding process and shell molding process, overcome these limitations.

1.2.2 Material Removal Processes

The class of manufacturing processes that use cutting or machining to remove excess material for producing the required shape, size, accuracy and finish are known as material removal processes or more commonly as machining processes. The removal of unwanted material from the raw material is done by using specific shaped cutting tools, operated manually or by machines called machine tools. With machining processes, it is possible to manufacture components with very low dimensional tolerances (accuracy and precision) that cannot be obtained by other methods of manufacturing but generate a lot of waste material from the removed portions as scrap. Typical examples of products made by machining processes include gears, automobile parts, wood furniture, nuts and bolts, etc. Examples of common machining processes include drilling, turning, milling, grinding, boring, knurling, facing, reaming, chamfering, etc. Machining is used as a secondary or subsequent process for many of the other manufacturing processes like casting, forming, etc.

1.2.3 Forming Processes

Manufacturing processes for giving the desired shape and size to raw material by permanently deforming it using force, pressure or stresses like compression, tension, shear or their combinations are known as forming processes. Unlike casting or machining, in forming, the material is neither melted nor removed. Forming processes exploit a property of materials – the ability to flow plastically (or deform) in the solid state (without melting) – when subjected to suitable stresses. The material is deformed to the desired shape and size with almost no wastage. The required force is generally high in forming processes, and the tools and equipment needed are quite expensive. Commonly, a machine for forming processes is known as a press, and forming tools used for the same are called a die and punch. Typical examples of the products manufactured by forming processes include rails, kitchen utensils, wires, drink cans, collapsible tubes and so on. No material wastage, a high cost of tooling and fast and easy large-quantity production of components are some of the characteristics of forming processes. Brittle material cannot be deformed plastically and, hence, cannot be formed. However, semi-brittle material can be formed using hot working (forming above the recrystallization temperature).

Blanking, punching, bending, stretching, rolling, forging, drawing, extrusion, spinning, etc., are some common forming processes. Forming processes are classified into two groups – bulk forming processes and sheet forming processes. The classification of forming processes is given in Figure 1.1.

FIGURE 1.1 Classification of forming processes.

Bulk forming involves severe deformation of material resulting in massive shape change. The surface-area-to-volume ratio of the workpiece is relatively small. Bulk forming is mostly done in hot working conditions. Some common bulk forming operations are forging, rolling, drawing and extrusion. Sheet forming processes are discussed in Section 1.3.

1.2.4 Joining Processes

The category of manufacturing processes where two or more workpieces are joined together to produce the required shape and/or siz...

Table of contents

• Cover
• Half-Title
• Title
• Copyright
• Contents
• List of Figures
• List of Tables
• Preface
• Acknowledgments
• Authors’ Biographies
• List of Abbreviations
• Chapter 1 Introduction and Need for Advanced Sheet Forming Techniques
• Chapter 2 Incremental Sheet Forming: A Die-Less Approach
• Chapter 3 Incremental Sheet Forming Process
• Chapter 4 Machine Tools and Forming-Tools for Incremental Sheet Forming Process
• Chapter 5 Incremental Sheet Forming Parameters
• Chapter 6 Responses of Incremental Sheet Forming Process
• Chapter 7 Applications and Challenges of Incremental Sheet Forming Processes
• Chapter 8 Conclusions and Future Scope
• Appendix A: List of US, Japanese (JP), European (EP) and International (WO) Patents Related to ISF
• Index