Famous people of science and engineering

Bill Gates

William Henry Gates was born in Seattle, Washing­ton, in 1955.

He is an American business executive, chairman and chief executive officer of the Microsoft Corporation. Gates was the founder of Microsoft in 1975 together with Paul Alien, his partner in computer language de­velopment. While attending Harvard in 1975, Gates together with Alien developed a version of the BASIC computer programming language for the first personal computer.

In the early 1980s. Gates led Microsoft's evolution from the developer of computer programming languages to a large computer software company. This transition began with the introduction of MS-DOS, the operating system for the new IBM Personal Computer in 1981. Gates also led Microsoft towards the introduction of application software such as the Microsoft Word proces­sor.

Much of Gates' success is based on his ability to trans­late technical visions into market strategy. Although Gates has accumulated great wealth from his holdings of Microsoft stock, he has been known as a tough competitor who seems to value winning in a competitive en­vironment over money. Gates still continues to work per­sonally in product development at Microsoft.

ALLOYS

Bronze and brass, the first alloys in the history of metallurgy, were probably obtained by man accidentally when melting mixed metal ores. Much later alloys of iron were obtained.

Steel was made in small quantities in early times un­til the mid-19th century when it was manufactured on a large scale in the iron and steel industry.

The commercial production of pure aluminium in about 1890 began a new range of alloys and among them duralumin, an alloy of about 94 per cent aluminium, with small quantities of copper, manganese, magnesium, and silicon. Most of aluminium alloys are both light and strong.

Nickel is often mixed with other metals for special purposes: permalloy is a nickel-iron alloy that is mag­netically soft. The polarity of its magnetic field can be easily changed and it is used for transformer cores. Monel metals contain about two parts nickel to one part cop­per, plus other elements. They are stronger than nickel and extremely corrosion-resistant. These properties make them useful in chemical production.

Electrum is a natural or artificial alloy of gold and sil­ver containing 15-45 per cent of silver. It was used in the ancient world for coinage.

Bismuth is frequently used as a part of alloys with low melting-points. Today alloys can be designed for particu­lar applications with certain properties.