A Good Solution Instead of an Optimal One

The objective of the present work, which was sponsored by the French Ministèrs de l'Industrie, is to save “vulnerable” metals, i.e., those for which supply is uncertain and/or those that have to be imported. The production of alloys at the lowest price from a number of stocks of scrap alloys of various composition and from unalloyed metals has been achieved through the use of a new algorithm built into a computer program. The method differs from the usual linear programming and avoids the shortcomings of the well-known algorithms. Results are given showing the profits foundries can achieve when using this algorithm. Finally, some practical aspects of the introduction of this software in a foundry are presented, with unexpected consequences on the replacement of used-up stocks.