Improvements in or relating to the production of magnesium and magnesium base alloy sections and sheets

摘要

601,388. Rolling magnesium ; altering physical structure. MAGNESIUM ELEKTRON, Ltd., and LISLE, A. B. May 18, 1945, Nos. 12555/45 and 14946/46. [Class 83 (iv)] A process for the production of sections or sheets of magnesium or magnesium base alloys comprises rolling a cast blank of at least one hundred square inches cross sectional area between pairs of rolls which substantially surround the metal the rolling in one or more of the passes being effected at speeds of at least fifty feet per minute and thereafter reheating and rolling into section or sheets. The thickness of the cast blank exceeds three inches and may be from five to twenty-five inches and may be reduced to 50 per cent by several passes through rolls which are grooved so that the blank is surrounded by the rolls except for relatively small gaps between the rolls. This treatment brings the blank into wrought condition in which it may be cut for rolling into sections or for cross rolling and final rolling down to the required thickness of sheet, for which operation normal plain rolls would be used. After the first entry into the rolls the speed may be from 100 to 600 feet per minute. Working at specifced temperatures.-A temperature of 500‹ C. is suitable for the initial rolling of the blank but in the later passes temperatures down to 200‹ C. or 250‹ C. may be used. Specifications 369,881, 511,137, [Group II], 542,576 and U.S.A. Specification 2,314,010 are referred to.