The art of material selection

The art of
Products achieve success through a combination of sound technical design and imaginative industrial design. The amalgam creates product character – the way material and processes are used to provide functionality, usability, and satisfaction in ownership. This last – satisfaction – is greatly influenced by the aesthetics, associations, and perceptions that the product carries, acombination that we shall refer to as product personality. The overall character of the product is a synthesis of its functionality, usability, and its personality. In this article we explore product personality and character, illustrating the ideas by analyzing a number of products, noting particularly how the choice of material and process has contributed.

materials selection
by Mike Ashby* andKara Johnson**
Good design works. Excellent design also gives pleasure. Pleasure derives from form, color, texture, feel, and the associations and perceptions that these invoke. Pleasing design says something about itself; generally speaking, honest statements are more satisfying than deception, though eccentric or humorous designs can be appealing too. Those who concern themselves with thesedimensions of engineering are known, rather confusingly, as ‘industrial designers’. This article introduces some of the ideas of industrial design, emphasizing the role of materials and the processes used to shape, join, and finish them.
But first a word of caution. Engineering design – design for technical function – follows well established and widely accepted procedures; it is systematic.Industrial design is not, in this sense, systematic; success, here, involves sensitivity to custom and educational background, and is influenced (manipulated, even) by fashion and advertising. Although there are many books on the subject of industrial design, you will find – it may surprise you – that they hardly mention the issues of functionality and efficiency, which are the central theme of texts onengineering design. They focus instead on qualities that cannot be measured: form, texture, proportion, and style; and on subtler things: creative vision, historic perspective, honesty to the qualities of materials. The views of this article are partly those of writers who seem to us to say sensible things, and partly our own1. You may not agree with them, but if they make you think about designingto give pleasure, then this article has done its job.

*Engineering Department, University of Cambridge, Trumpington Street, Cambridge, CB2 1PZ, UK Royal College of Art, Kensington Gore, London, SW7 2EU, UK E-mail: mfa2@eng.cam.ac.uk **IDEO, 100 Forest Avenue, Palo Alto, CA 94301, USA E-mail: kjohnson@ideo.com

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December 2003

REVIEW FEATURE

Aesthetics, associations, perceptionsThe pen with which I am writing this page cost $5 (Fig. 1, upper image). If you go to the right shop you can find a pen that costs well over $1000 (lower image). Does it write 200 times better than mine? Unlikely; mine writes perfectly well. Yet there is a market for such pens. Why? A product has a cost, C, the outlay in manufacture and marketing. It has a price, P, the sum at which it is offeredto the consumer. And it has a value, V, a measure of what the consumer thinks it is worth. For a product to succeed in the market place it is necessary that, C V no one will buy it. The greater the value, the larger the price that can be charged without infringing the inequalities in the equation; and the larger the difference between price and cost, the larger the profit. Cost is determined by thetechnical design of the product and the choice of materials and processes used to make it. But what determines value? Functionality, provided by sound technical design, clearly plays a role. But a greater role is that of industrial design: the concern for the aesthetics of the product, the associations and perceptions it carries. We will elaborate on these in a minute; first a closer look at...