CPC B21D 53/16 (2013.01) [B21J 5/02 (2013.01); C22C 9/02 (2013.01)] | 9 Claims |
1. A method for forming a QCr0.8 alloy tapered cylindrical ring, comprising:
(S1) heating a raw material to 750-850° C. followed by upsetting and stretching at least twice to obtain a primary blank;
wherein the raw material is a standard cylindrical part made of QCr0.8 alloy;
(S2) heating the primary blank to 750-850° C. followed by upsetting and chamfering to obtain a secondary blank with a top end and a bottom end; wherein a diameter of the top end of the secondary blank is greater than a diameter of the bottom end of the secondary blank;
(S3) subjecting the secondary blank to backward extrusion to process the top end and the bottom end of the secondary blank to obtain a preform;
(S4) machining the preform to remove a flash and a bottom residue of the preform;
(S5) subjecting a bottom end of the preform to local bulging to enable a shape and a size of the bottom end of the preform to match a shape and a size of a drive roller in a forming tooling, so as to form a profiled ring blank; and
(S6) rolling the profiled ring blank by using a radial-axial ring rolling machine in combination with the forming tooling to form a tapered cylindrical ring;
wherein the step (S3) is performed through steps of:
heating the secondary blank to 750-850° C. at a heating coefficient of 0.4-0.6 min/mm;
subjecting the secondary blank to one-step extrusion molding on a press machine; and
performing air cooling after forging to form the preform with a cone angle of 40-90° and a bottom diameter of Φ330-480 mm;
wherein a final forging temperature is not less than 650° C.
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