INFLUENCE OF NICKEL ON THE SOLIDIFICATION PROCESS IN STAINLESS STEELS CONTAINING 18. 5P OF CHROMIUM/ INFLUENCE DU NICKEL SUR LE DEROULEMENT DE LA SOLIDIFICATION D'ACIERS INOXYDABLES CONTENANT 18,5P DE CHROME.

THE SOLIDIFICATION OF STAINLESS STEELS CONTAINING APPROXIMATELY 18. 5P CHROMIUM AND CONSTANT AMOUNTS OF SOME MINOR ELEMENTS (CARBON, SILICON, SULFUR, PHOSPHORUS, MANGANESE AND NITROGEN) WAS INVESTIGATED BY MEANS OF DTA. QUENCHING OF THE SPECIMENS DURING SOLIDIFICATION MADE IT POSSIBLE TO IDENTIFY THE PHASES FORMED AND TO DETERMINE THE PROPORTION OF PHASES AND THEIR DEVELOPMENT WITH TEMPERATURE. A CORRELATION WAS ESTABLISHED BETWEEN THE NATURE OF THE FIRST SOLID FORMED FROM THE LIQUID STEEL ( ″DELTA″ -OR ″GAMMA″ -PHASE) AND THE CONTENT OF NICKEL. THE EXPERIMENTAL DATA SHOWED GOOD AGREEMENT WITH THE RESULTS OF CALCULATIONS PERFORMED FOR MICROSEGREGATIONPROCESSES IN THE STEELS INVESTIGATED. IN FRENCH.