KNIFE THAT LAY IN GARDEN

Taranaki Daily News, 4 August 1934, Page 10 (Supplement)

KNIFE THAT LAY IN GARDEN

BRIGHT METAL WOULD NOT DIM. STORY OF STAINLESS STEEL. A wonderful story has just been told which proves how alert our scientists are to to notice the slightest hint of new development. It demonstrates how a faiure in one direction may lead to discovery in another. Our stainless owes its origin to a failure in solving one of the perplexing problems of erosion. During the war a metallurgist named Mr. Harry Brearley was testing steels with a view to improving the resistance to erosion of the steel that is used in the making of rifle barrels. In one test he made a piece of steel which had a large proportion of chromium, more than had ever been used before. It proved unsuitable for the rifle, so he broke it in two and threw it into a corner of his laboratory where similar failures lay in semi-obscurity.

A fortnight later one of his assistants called his attention to the fact that two of the test pieces were still bright. All the others had rusted, but these pieces had not changed. Mr. Brearley remembered that these were the broken pieces of the steel containing the large proportion of chromium. He tried to etch it with acid and found that it was resistant, and at once he knew that he had in his hand a new steel with great possibilities. Owing to his war work Mr. Brearley Was exceedingly busy, but he found a few moments to have a knife-blade forged containing the same proportion of chromium. This he left exposed to the weather in his garden for a month, and found that it was still bright.

It was not possible to develop the discovery at the time, but when the war was over the new process was perfected, and the stainless steel now in everyday use was placed on the market.