Usinor

Fr&eacute;d&eacute;ric Mazurier

Jean-Michel Damasse

Christian Marchionni

Philippe Paradis

Fr&eacute;d&eacute;ric Descaves

The invention concerns a method for continuously casting an austenitic stainless steel strip with a thickness not more than 10 mm, directly from liquid metal, between two cooled horizontal rolls, characterised in that: said steel composition in weight proportions comprises: %C&lE;0.08%; %Si&lE;1; %P&lE;0.04; %Mn&lE;2; %Cr between 17 and 20; %Ni between 8 and 10.5; %S between 0.007 and 0.040; the rest being iron and the impurities resulting from preparation; the ratio Cr /Ni ranges between 1.55 and 1.90 with: Cr (%)&equals;%Cr&plus;1.37 %Mo&plus;1.5 %Si&plus;2%Nb&plus;3 %Ti; Ni (%)&equals;%Ni&plus;0.31 %Mn&plus;22 %C&plus;14.2 %N&plus;Cu; the surface of the rolls comprises contiguous dimples with more or less circular or elliptical cross-section, of diameter between 100 and 1500 &mgr;m and depth between 20 and 150 &mgr;m; the inerting gas surrounding the meniscus is a gas soluble in steel or a mixture of such gases, or consists of at least 50% by volume of such a gas or mixture of gases.

Method for continuously casting between two rolls austenitic stainless steel strips with excellent surface quality and resulting strips

The invention concerns a method for continuously casting a ferritic stainless steep strip with thickness not more than 10 mm directly from liquid metal between two cooled rolls with horizontal axes and driven in rotation, characterized in that: the liquid metal composition in weight percentages is as follows: % C&plus;% N&lE;0.12; % Mn&lE;1; % P&lE;0.4; % Si&lE;1; % Mo&lE;2.5; % Cr between 11 and 19; A1&lE;1%; % Ti&plus;%Nb&plus;% Zr&lE;1; the rest being iron and the impurities resulting from preparation; the &Ugr; index of the liquid metal ranges between 35% and 60%, &Ugr; being defined by the formula: &ggr; &equals;420% C&plus;470% N&plus;23% Ni&plus;9% Cu&plus;7% Mn 11.5% Cr 11.5% Si 12% Mo 23% V 47% Nb 49% Ti 52% A1&plus;189: the surface roughness of said rolls being more than 5 &mgr;m; in the proximity of the meniscus metal liquid present between the rolls an inerting gas is used consisting of at least 60% by volume of a gas soluble in steel.

Growing community of inventors

Bethune, France

Frédéric Mazurier

Growing community of inventors

Bethune, France

Fr&eacute;d&eacute;ric Mazurier

Frédéric Mazurier