Effect Of Solid Solution Treatment On Microstructures And Properties Of 2026 Aluminum Alloy

Deformation and heat treatment is an effective way to control the internal structure and properties of aluminum alloy.One of the main gaps in the development and application of aluminum alloy between China and European and American countries is that lack of systematic research on deformation and heat treatment process.This paper studies the solution process of 2026 aluminum alloy developed by Alcoa in 2001,and the effect of solution process on the structure and properties of 2026 aluminum alloy,The purpose of this study is to reveal the evolution rule of the structure of the alloy under different solution systems,and It provides a reference for the optimization of the alloy preparation process.The specific research contents include:(1)Influence of solution treatment on the structure of 2026 aluminum alloy;(2)According to the structure and properties,determining the typical process system,analyzing the tensile fracture,and studying the internal mechanism.The results show that:(1)During the solid solution process at 480?-555? for 60 min,2026 aluminum alloy extruded bar was partially recrystallized at 540? and completely recrystallized at 555?.The remelting ball appears at 520? and with the increase of temperature,the remelting ball becomes larger The strength and elongation of the samples increased and then decreased with the increase of solution temperature.The yield strength and tensile strength were the highest at 520?(409 MPa and 588 MPa,respectively),and the elongation was the highest at 510?(17.1%).(2)During the solution process at 555? for different holding time(5 min-60 min),the sample locally recrystallized but not overburned when it was kept for 5 min;when it was kept for 10 min,the sample obviously recrystallized and slightly overburned;and The degree of recrystallization and overburning increased with the increase of holding time.The yield strength and tensile strength of elongation decreased with the increase of holding time,The tensile properties of the samples were the best when they were kept for 5 min,yield strength,tensile strength and elongation were 418 MPa,587 MPa and 19.4%,respectively.(3)The heating rate is about 280?/min.when the aluminum alloy 2026 is heated in an induction furnace and kept for 5 min,partial recrystallization occurs at 480?and complete recrystallization occurs at 540?.However,severe overburning occurs in the samples kept at 480?,520? and 540?.(4)After holding for 5 min at 500? with different heating rates(20?/min-169?/min),local recrystallization occurs to some extent when the heating rate is above 56?/min,and the samples take place slightly over-burning when the heating rate reaches 169?/min.The heating rate(20?/min-169?/min)has little effect on the yield strength and tensile strength of 2026 aluminum alloy,but the elongation of the material increases from 16.5%to 18.5%when the heating rate is increased to 56?/min.(5)When 2026 aluminum alloy undergoing slight over-burning,it has little effect on the mechanical properties of the material.However,the tensile properties of the material decrease significantly with a lot of remelting balls and remelting grain boundaries in the alloy.The increase of recrystallization degree is conducive to the improvement of the elongation of 2026 aluminum alloy on the premise of without over-burning,while the effect is limited on the tensile strength of the material.