Method of preparing iron silicon alloys with high silicon content for cold working requiring ductility

Claim 1

METHOD OF WORKING IRON SILICON STEEL ALLOYS HAVING SILICON CONTENT BETWEEN 4.5% TO 7.5% BY WEIGHT, THE REMAINDER BEING IRON AND IMPURITIES, PROVIDING THE STEPS OF: FIRST, HOT WORKING A CASTING OF SAID ALLOY AT A TEMPERATURE IN EXCESS OF 650* CENTRIGRADE TO OBTAIN A FIRST INTERMEDIATE PRODUCT; SECOND, WORKING AND FORMING THE FIRST INTERMEDIATE PRODUCT INTO A SECOND INTERMEDIATE PRODUCT DURING COOLING FROM 650*C DOWN TO AT LEAST 350*C PRIOR TO FINAL WORKING, AND THIRD, MAKING PARTS FROM THE UNANNEALED SECOND INTERMEDIATE PRODUCT WHICH HAS NOT BEEN REHEATED ABOVE 350*C AND WHILE AVOIDING INCREASING ITS TEMPERATURE ABOVE 350* C, THE MAKING OF PARTS IN ACCORDANCE WITH THE THIRD STEP EXCLUDING ROLLING AND BEING OF THE VARIETY WHICH IS IMPEDED BY BRITTLENESS BECAUSE OF FORMATION OF EDGE CRACKS AND BURRS, AND BEING ONE OF THE FOLLOWING CUTTING, PUNCHING, STAMPING, THE BRITTLENESS HAVING BEEN MAINTAINED SUFFICIENTLY LOW BY THE SECOND STEP AND BY MAINTAINING THE TEMPERATURE BELOW 350*C, SO THAT CRACKS AND BURRS ARE AVOIDED DURING THE CUTTING, PUNCHING OR STAMPING FOR MAKING SUCH PARTS.

Claim 11

A method for preparing silicon steel sheet stock with a silicon content in-between 4.5 % and 7.5 % by weight for making parts by stamping, punching or cutting from such sheet stock, such making requiring ductility and low brittleness and resulting in the formation of cracks and burrs along the edges when the sheet stock used is too brittle, comprising the steps of: hot rolling a cast ingot into a plate or sheet bar at a temperature in excess of 650* C; rolling the plate or sheet bar into sheet stock in plural passes during cooling of The plate or sheet bar from a temperature above 650* C, and at such rate and strength that the forming lattice structure is continuously disturbed and a uniform flow is maintained during each pass at least until the temperature has dropped below 425* C to reduce the brittleness of the resulting sheet stock; and maintaining the resulting low brittleness by keeping the temperature of the sheet stock below 350* C and avoiding re-heating above that temperature, at least until after stamping, punching or cutting parts from the sheet stock as succeeding any and all rolling of said sheet stock.

Claim 12

A method for preparing silicon steel sheet stock with a silicon content in-between 4.5 % and 7.5 % by weight for making parts by stamping, punching or cutting from such sheet stock, such making requiring ductility and low brittleness and resulting in the formation of cracks and burrs along the edges when the sheet stock used is too brittle, comprising the steps of: hot rolling a cast ingot into a plate or sheet bar at a temperature in excess of 650* C; rolling the plate or sheet bar into sheet stock in plural passes during cooling of The plate or sheet bar from a temperature above 650* C, and at such rate and strength that the forming lattice structure is continuously disturbed and a uniform flow is maintained during each pass at least until the temperature has dropped below 425* C to reduce the brittleness of the resulting sheet stock; and maintaining the resulting low brittleness by keeping the temperature of the sheet stock below 350* C and avoiding re-heating above that temperature, at least until after stamping, punching or cutting parts from the sheet stock as succeeding any and all rolling of said sheet stock.