Effect of cooling rate on precipitation during homogenization cooling in an excess silicon AlMgSi alloy

被引：34

作者：

Birol, Yucel ^{[1
]}

机构：

[1] TUBITAK, Marmara Res Ctr, Mat Inst, Kocaeli, Turkey

来源：

MATERIALS CHARACTERIZATION | 2012年 / 73卷

关键词：

Aluminum alloys; Extrusion; Heat treatment; MICROSTRUCTURE CONTROL; SI; EXTRUDABILITY; TEMPERATURE; EXTRUSION; SEQUENCE; PHASES;

D O I：

10.1016/j.matchar.2012.07.015

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

The effect of cooling rate on the precipitation process during homogenization cooling in EN AW 6082 alloy was investigated. The extent of precipitation was estimated from electrical conductivity measurements on samples cooled to room temperature at different rates. There is considerable amount of precipitation during cooling even at 1000 degrees C h(-1). The precipitating phase is predominantly the equilibrium beta-Mg2Si. The hardness decreases while the extent of precipitation increases with decreasing cooling rate, particularly below 250 degrees C h(-1), where orthogonal beta'-Mg2Si platelets, in addition to beta-Mg2Si, form. A considerable fraction of the precipitation capacity is retained at the end of homogenization cooling at rates relevant to the industrial practice. Billets respond to a subsequent preheating cycle by beta as well as beta' precipitation. The metastable beta '' phase, on the other hand, is suppressed. Cooling rates between 1000 and 150 degrees C h(-1) have no impact on the dissolution behavior during billet preheating. All billets undergo complete dissolution at 475 degrees C implying that there may be possibilities of exploring lower preheating temperatures than what is normally used in the processing of EN AW 6082 billets. (C) 2012 Elsevier Inc. All rights reserved.

引用

页码：37 / 42

页数：6

共 28 条

[1]

Beatty E. C, 1977, P 2 INT AL EXTR TECH, P225

[2]

Beatty EC, 1969, P 1 INT AL EXTR TECH

[3] The effect of processing and Mn content on the T5 and T6 properties of AA6082 profiles [J].

Birol, Y .

JOURNAL OF MATERIALS PROCESSING TECHNOLOGY, 2006, 173 (01) :84-91

[4]

Birol Y, 2004, J MATER PROCESS TECH, V148, P250, DOI [10.1016/j.jmatprotec.2004.01.056, 10.1016/j.matprotec.2004.01.056]

[5]

Birol Y, MAT CHEM PHYS UNPUB

[6] The influence of homogenisation cooling rate, billet preheating temperature and die geometry on the T5-properties for three 6XXX alloys extruded under industrial conditions [J].

Bjornbakk, EB ;

Sæter, JA ;

Reiso, O ;

Tundal, U .

ALUMINUM ALLOYS 2002: THEIR PHYSICAL AND MECHANICAL PROPERTIES PTS 1-3, 2002, 396-4 :405-410

[7] Calorimetric study of 6061-Al-15 vol.% SiCw PM composites extruded at different temperatures [J].

Borrego, A ;

Gonzalez-Doncel, G .

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING, 1998, 245 (01) :10-18

[8] Analysis of the intermetallic phase transformation occurring during homogenization of 6xxx aluminum alloys [J].

Claves, SR ;

Elias, DL ;

Misiolek, WZ .

ALUMINUM ALLOYS 2002: THEIR PHYSICAL AND MECHANICAL PROPERTIES PTS 1-3, 2002, 396-4 :667-674

[9]

Dahl N, 1996, P 6 INT AL EXTR TECH, V1, P529

[10] The precipitation sequence in Al-Mg-Si alloys [J].

Edwards, GA ;

Stiller, K ;

Dunlop, GL ;

Couper, MJ .

ACTA MATERIALIA, 1998, 46 (11) :3893-3904

← 1 2 3 →