Solid Freeform Fabrication

Abstract

This research document mentions the commonly used techniques for Solid Freeform Fabrication or Rapid Prototyping. It discusses comparison of solid freeform fabrications methods or techniques. It discusses the basic principles of working of different SFF techniques. The research document enlightens the capabilities of 3D printing. It also enlightens the products of 3D printing in international market and the different types of applications of 3D printing.

Introduction

Solid freeform fabrication (SFF) is a technique for manufacturing solid objects by the sequential delivery of energy and/or material to specified points in space to produce that solid. SFF is sometimes referred to as rapid prototyping, rapid manufacturing, layered manufacturing and additive fabrication.

Prototypes are an essential part of the research and development process for engineers. They allow pre-production testing and serve to highlight potential problems within a design. In the past, producing a prototype model has been a very expensive process, relying on traditional machining processes more suited to producing large numbers of a single product. The use of these processes increases the time taken for an original idea to reach the consumer as a finished product.

The speed of the production of prototypes was greatly increased by the introduction of Computer Numerically Controlled (CNC) Machining, reducing waiting time for a prototype to a few days or weeks.

More recently, Rapid Prototyping systems have been developed which are capable of producing a part in as little as a few hours.

The Basic Principles of Solid Freeform Fabrication

In order to create a part by any Rapid Prototyping process, it is first necessary to create a 3D drawing of the object using CAD software. The computer then divides the drawing into layers and gives the RP machine a description of each individual layer.

A piece of artwork created by Solid Freeform Fabrication

The machine then creates these layers, one on top of the other, to produce a whole part. In some cases it is then necessary to finish the part by hand (i.e. by sanding of painting it).

There are various types of Rapid Prototyping, several of which are described in greater detail below. The main difference between these systems is the method they use to lay down or create the layers.

The systems also use different types of materials to produce the models. Materials include thermoplastics, wax, ceramics, metals and, most commonly, polymers. In stereolithography liquid acrylic polymer is used to form models, while laminated object manufacturing uses paper or plastic sheets.

Techniques