Forging process for an aluminum alloy part

Abstract

An forging process for an aluminum alloy part. The forging process includes the following steps: S 1 , heating an aluminum alloy blank to a solid solution temperature in a heating device, where, a heating and heat preservation time is determined according to a wall thickness of the aluminum alloy blank and prolonged by 20 min when the wall thickness of the aluminum alloy blank is increased by 1 mm; S 2 , conducting underaging heat treatment; S 3 , conducting heating and heat preservation on the aluminum alloy blank obtained after the underaging heat treatment with a forging die at 100-300° C., and preheating a final forging die; S 4 , conducting forming by isothermal forging on the aluminum alloy blank obtained after the heating and heat preservation in step S 3 at 100-300° C.; and S 5 , conducting cooling, trimming and machining on a forged part obtained in step S 4 to obtain the aluminum alloy part.

What is claimed is: 
     
         1 . A forging process for an aluminum alloy part, comprising the following steps:
 S 1 , heating an aluminum alloy blank to a solid solution temperature in a heating device, wherein, a heating and heat preservation time is determined according to a wall thickness of the aluminum alloy blank and prolonged by 20 min when the wall thickness of the aluminum alloy blank is increased by 1 mm;   S 2 , conducting pre-forging forming after step S 1 , wherein, a pre-forging die is heated to a forging temperature, and the aluminum alloy blank is cooled to a pre-forging temperature of 200-450° C. and subjected to the pre-forging forming;   S 3 , conducting underaging heat treatment at a temperature of 100-300° C., wherein, a heat preservation time is controlled within 2-8 h, and a specific temperature is determined according to a position of an exothermic peak precipitated in a corresponding GP zone to ensure that after the underaging heat treatment, a precipitated phase only has the GP zone and few β″ phases;   S 4 , conducting heating and heat preservation on the aluminum alloy blank obtained after the underaging heat treatment at 100-300° C., and preheating a final forging die;   wherein, a heat preservation temperature and a final forging temperature are determined according to a position of an exothermic peak precipitated in a corresponding β″ zone, the temperature is controlled to ensure that a β′ phase is not further precipitated, and the heat preservation is conducted within 1-10 min;   S 5 , conducting final forging forming by isothermal forging on the aluminum alloy blank obtained after the heating and heat preservation in step S 4  at 100-300° C.; and   S 6 , conducting cooling, trimming and machining on a forged part obtained in step S 5  to obtain the aluminum alloy part.   
     
     
         2 . The forging process of  claim 1 , wherein, the aluminum alloy is a 6,000 series aluminum alloy. 
     
     
         3 . The forging process of  claim 1 , wherein, in step S 4 , the final forging die is preheated at a temperature of 200° C.