Aluminum 6061, Al 6061-T6 Alloy Properties, Density, Tensile & Yield Strength, Thermal Conductivity, Modulus of Elasticity, Welding

6061 Aluminum Alloy (Al 6061-T6, 6061-T651, 6061-T4)

Al-6061 aluminum alloy is a general purpose structural alloy developed by Alcoa in 1935. The temper designations mainly have 6061-T4, T451, Al 6061-T6, 6061-T651, etc. It is one of the most widely used alloys. The main alloying elements are magnesium (Mg) and silicon (Si). The content of silicon and magnesium in this alloy is close to form magnesium silicide (Mg2Si), so it is a heat-treated wrought alloy.

Aluminum 6061-T6 has a minimum yield strength of 35 ksi (240 MPa), which is almost equal to that of A36 steel. This strength, combined with its light weight (about 1/3 that of steel), makes it particularly suitable for structural applications where static loads are a concern. Compared to 7000 (e.g. alloy 7075) and 2000 series (e.g. alloy 2024) aluminum, AA6061, although lower in strength, is less sensitive to solution heat treatment and quench variation.

Because 6061 aluminium alloy is easy to extrude, it can provide a variety of product forms such as sheet, strip, plate, rod, forgings, tubes, pipes, wires, extruded parts and structural shapes.

Aluminum 6061 has good corrosion resistance, mechanical properties, formability, weldability, and machinability. Generally suitable for medium to high strength requirements, and has good toughness. Applications range from food and beverage packaging, electronic products and home appliances, architectural decoration, transportation to aerospace components. Alloy 6082, popular in Europe, is slightly stronger than AA6061 and has similar uses.

The abbreviations Al-6061 and AA6061 in this article are the same material. Al-Aluminum; AA-the Aluminum Association or Aluminum Alloy.

Aluminum Alloy 6061 Properties, Data Sheet & Specs.

The following tables and lists summarize 6061 aluminum properties, datasheet and specs including chemical composition, physical properties and mechanical properties, welding, hardness, machinability, heat treating, etc.

Chemical Composition

Aluminium 6061 chemical composition is listed in the following table.

AA-6061 Chemical Composition, %
ASTM, SAE AMS	ANSI, Alloy (UNS)	Si	Fe, ≤	Cu	Mn, ≤	Mg	Cr	Zn, ≤	Ti, ≤	Other Elements, Each (Total), ≤	Al
ASTM B209; ASTM B211; ASTM B221; ASTM B210; ASTM B308/B308M; ASTM B308/B308M; ASTM B308/B308M; ASTM B241/B241M; SAE AMS 4025; SAE AMS 4026; SAE AMS 4027; SAE AMS 4117	6061 (UNS A96061)	0.4-0.8	0.7	0.15-0.40	0.15	0.8-1.2	0.04-0.35	0.25	0.15	0.05 (0.15)	Remainder

Notes (various standards of 6061 aluminum):

• ASTM B209: Aluminum and Aluminum-Alloy Sheet and Plate.
• ASTM B211: Rolled or Cold Finished Bar, Rod, and Wire.
• ASTM B221: Extruded Bars, Rods, Wire, Profiles and Tubes.
• ASTM B210: Aluminum and Aluminum-Alloy Drawn Seamless Tubes.
• ASTM B308/B308M: AL 6061-T6 Aluminum Structural Profiles.
• ASTM B241/B241M: Seamless Pipe and Seamless Extruded Tube.
• SAE AMS 4025: Sheet and Plate; Temper O; Annealed.
• SAE AMS 4026: Sheet and Plate; Temper T4, T42, T451 (-T4 Sheet, -T451), Solution Heat Treated and Naturally Aged.
• SAE AMS 4027: Sheet and Plate; Temper T6 Aluminum, T62, T651 (AL 6061-T6 Sheet, 6061T651 Plate) Solution and Precipitation Heat Treated.
• SAE AMS 4117: Rolled or Cold Finished Bars, Rods, and Wire and Flash Welded Rings; (AL 6061-T6 Aluminum, 6061-T651).

6061 Aluminum Physical Properties

6061 aluminum physical properties are given in the following lists, including density, melting point, coefficient of thermal expansion, elastic modulus, thermal conductivity, specific heat capacity electrical conductivity, and electrical resistance.

Notes:

• 10^-6·K^-1 = 10^-6/K = 1 μm/m·°C
• 1 Ω·mm²/m = 1 μΩ·m
• 1 g/cm3 = 1 kg/dm3 = 1000 kg/m3
• 1 GPa = 1 kN/mm2
• 1 MPa = 1 N/mm2

The melting range shown applies to wrought products with a thickness of 6.35 mm (1/4 in.) or greater.

Specific gravity: 2.7

Al-6061 Aluminum Physical Properties
ASTM	Alloy and Temper	Density, g/cm3 (lb/in.3)	Melting point, °C (°F)	Specific heat capacity, J/kg·K (Btu/lb ·°F)	Coefficient of thermal expansion, 10-6/K (μin./in. ·°F)	Thermal diffusivity, mm2/s	Thermal conductivity, W/m·°C (Btu∙in/h∙ft²∙°F)	Electrical conductivity, Equal volume (Equal weight), % IACS	Electrical resistivity, Ω·mm2/m (Ω· circ mil/ft)
ASTM B209; ASTM B210; ASTM B221; ASTM B241; ASTM B308; SAE AMS 4027; SAE AMS 4117; SAE AMS 4025; SAE AMS 4026	6061-O	2.70 (0.098)	580-650 (1080-1205)	896 (0.214) at 20 °C (68 °F)	23.6 (13.1) at 20-100 °C (68-212 °F)	66	180 (1250) at 25 °C (77 °F)	47 (155) at 20 °C (68 °F)	0.0365 (22) at 20 °C (68 °F)
	6061-T4						154 (1070) at 25 °C (77 °F)	40 (132) at 20 °C (68 °F)	0.043 (26) at 20 °C (68 °F)
	6061-T6						167 (1160) at 25 °C (77 °F)	43 (142) at 20 °C (68 °F)	0.040 (24) at 20 °C (68 °F)

Mechanical Properties

Aluminium 6061-T6 mechanical properties are listed in the following tables including yield strength (yield stress), ultimate tensile strength, shear strength, modulus of elasticity, young’s modulus, etc.

The following mechanical properties is the average value of various sizes, product forms and manufacturing methods, so the properties cannot be guaranteed. They are only used as a basis for comparing alloys and tempering, and should not be specified as engineering requirements or used for design purposes.

Aluminum 6061 Mechanical Properties, Part-1
Aluminum Alloy and Temper	Ultimate Tensile strength, MPa (ksi)	Yield strength, MPa (ksi)	Elongation in 50 mm (2 in.), ≥%		Brinell Hardness, HB (500 kgf load 10 mm ball)
			1.6mm (1/16 in.) thick specimen	12.5mm (1/2 in.) thick specimen
6061-O	125 (18)	55 (8)	25	27	30
6061-T4, T451	240 (35)	145 (21)	22	22	65
6061-T6, T651	310 (45)	275 (40)	12	15	95
Alclad 6061-O	115 (17)	50 (7)	25	–	–
Alclad 6061-T4, T451	230 (33)	130 (19)	22	–	–
Alclad 6061-T6, T651	290 (42)	255 (37)	12	–	–

Aluminum 6061 Mechanical Properties, Part-2
Aluminum Alloy and Temper	Ultimate shear strength, MPa (ksi)	Modulus of elasticity, GPa (106 psi)	Fatigue endurance limit, MPa (ksi)
6061-O	85 (12)	69 (10)	60 (9)
6061-T4, T451	165 (24)	69 (10)	95 (14)
Al 6061-T6, T651	205 (30)	69 (10)	95 (14)
Alclad 6061-O	75 (11)	69 (10)	–
Alclad 6061-T4, T451	150 (22)	69 (10)	–
Alclad 6061-T6, 6061-T651	185 (27)	69 (10)	–

Notes for modulus of elasticity: The average of the tensile (Young’s modulus) and compressive modulus. The compression modulus is about 2% higher than the tensile modulus (Young’s modulus).

Aluminum 6061 Typical Mechanical Properties at Different Temperatures
Alloy and temper	Temperature, °C (°F)	Ultimate tensile strength, MPa (ksi)	0.2% offset yield strength	Elongation in 50 mm (2 in.), ≥%,
6061-T6, 6061-T651	-195 (-320)	415 (60)	325 (47)	22
	-80 (-112)	338 (49)	290 (42)	18
	0 (-18)	325 (47)	283 (41)	17
	24 (75)	310 (45)	275 (40)	17
	100 (212)	290 (42)	262 (38)	18
	150 (300)	235 (34)	215 (31)	20
	205 (400)	130 (19)	103 (15)	28
	250 (500)	52 (7.5)	35 (5)	60
	315 (600)	32 (4.6)	19 (2.7)	85
	370 (700)	21 (3)	12 (1.8)	95

Mechanical Properties of Aluminum 6061-T6 in SAE AMS and ASTM Standard

Aluminium 6061 Mechanical Properties – Extruded Bars, Rods, Wire, Profiles, and Tubes
Standard	Aluminum Alloy and Temper	Specified Diameter or Thickness, in.	Area, in2	Tensile Strength, ksi, ≥ (unless otherwise specified)	Yield Strength (0.2 % offset), ksi, ≥ (unless otherwise specified)	Elongation in 2 in. or 4xDiameter, ≥, %
ASTM B221	6061-O	all	all	22, ≤	16, ≤	10
	6061-T1	≤ 0.625	all	26.0	14.0	16
	6061-T4, T4510, T4511	all	all	26.0	16	16
	6061-T42	all	all	26.0	12	16
	6061-T51	≤ 0.625	all	35.0	30	8
	6061-T6, T62, T6510, T6511	≤ 0.249	all	38	35	8
		≥0.250	all	38	35	10

Aluminium 6061 Mechanical Properties – Drawn Seamless Tubes					Elongation in 2 in. or 4xDiameter, ≥, %
Standard	Aluminum Alloy and Temper	Specified Diameter or Thickness, in.	Tensile Strength, ksi, ≥ (unless otherwise specified)	Yield Strength (0.2 % offset), ksi, ≥ (unless otherwise specified)	Full-Section Specimen	Cut-Out Specimen
ASTM B210; AMSWWT700/6	6061-O	0.018-0.500	22, ≤	14, ≤	15	15
	6061-T6, T62	0.025-0.049	30.0	16.0	16	14
		0.050-0.259	30.0	16.0	18	16
		0.260-0.500	30.0	16.0	20	18
	6061-T42	0.025-0.049	30.0	14.0	16	14
		0.050-0.259	30.0	14.0	18	16
		0.260-0.500	30.0	14.0	20	18
	6061-T6, T62	0.025-0.049	42.0	35.0	10	8
		0.050-0.259	42.0	35.0	12	10
		0.260-0.500	42.0	35.0	14	12

Aluminium 6061 Mechanical Properties – Rolled or Cold Finished Bar, Rod, and Wire
Standard	Aluminum Alloy and Temper	Specified Diameter or Thickness, in.	Tensile Strength, ksi, ≥ (unless otherwise specified)	Yield Strength (0.2 % offset), ksi, ≥ (unless otherwise specified)	Elongation in 2 in. or 4xDiameter, ≥, %
ASTM B211	6061-O	≤0.124	20, ≤	–	–
		0.125-8.000			18
	6061-T4, T451	≤ 0.124	30	–	–
		0.125-8.000	30	16	18
	6061-T42	0.125-8.000	30	14	18
	6061-T6, T62, T651	≤ 0.124	42	–	–
		0.125-8.000	42	35	10
	6061-T89, T94	≤ 0.374	54	47	–

Aluminium 6061 Mechanical Properties – Plate and Sheet
Standard	Aluminum Alloy and Temper	Specified Thickness, in.	Tensile Strength, ksi, ≥ (unless otherwise specified)	Yield Strength (0.2 % offset), ksi, ≥ (unless otherwise specified)	Elongation in 2 in. or 4xDiameter, ≥, %	Bend Diameter Factor, N
ASTM B209	6061-O	0.006-0.007	≤22	12.0	10	0
		0.008-0.009			12	0
		0.010-0.020			14	0
		0.021-0.128			16
		0.129-0.249			18	1
		0.250-0.499			18	2
		0.500-1.000			18	3
		1.001-3.000			16	–
	6061-T4	0.006-0.007	30.0	16.0	10	2
		0.008-0.009			12	2
		0.010-0.020			14	2
		0.021-0.249			16	3
	6061-T451	0.250-0.499	30.0	16.0	18	4
		0.500-1.000			18	–
		1.001-3.000			16	–
	6061-T42	0.006-0.007	31.0	14.0	10	2
		0.008-0.009			12	2
		0.010-0.020			14	2
		0.021-0.249			16	3
		0.250-0.499			18	4
		0.500-1.000			18	–
		1.001-3.000			16	–
	6061-T6, T62	0.006-0.007	42.0	35.0	4	2
		0.008-0.009			6.0	2
		0.010-0.020			8.0	2
		0.021-0.036			10.0	3
		0.037-0.064			10.0	4
		0.065-0.128			10.0	5
		0.129-0.249			10.0	6
	6061-T62, T651	0.250-0.499	42.0	35.0	10	7
		0.500-1.000	42.0		9	–
		1.001-2.000	42.0		8	–
		2.001-4.000	42.0		6	–
		4.001-6.000	40.0		6	–
	6061 F	0.250-3.000	–	–	–	–
	Alclad 6061-O	0.010-0.020	≤20	12.0	14	–
		0.021-0.128	≤20	12.0	16	–
		0.129-0.499	≤20	12.0	18	–
		0.500-1.000	≤22	–	18	–
		1.001-3.000	≤22	–	16	–
	Alclad 6061-T4	0.010-0.020	27.0	14.0	14	–
		0.021-0.249	27.0	14.0	16	–
	Alclad 6061-T451	0.250-0.499	27.0	14.0	18	–
		0.500-1.000	30.0	16.0	18	–
		1.001-3.000	30.0	16.0	16	–
	Alclad 6061-T42	0.010-0.020	27.0	12.0	14	–
		0.021-0.249	27.0	12.0	16	–
		0.250-0.499	27.0	12.0	18	–
		0.500-1.000	30.0	14.0	18	–
		1.001-3.000	30.0	14.0	16	–
	Alclad 6061-T6, T62	0.010-0.020	38.0	32.0	8	–
		0.021-0.249	38.0	32.0	10	–
	Alclad 6061-T6, T62	0.250-0.499	38.0	32.0	10	–
		0.500-1.000	42.0	35.0	9	–
		1.001-2.000	42.0	35.0	8	–
		2.001-4.000	42.0	35.0	6	–
		4.001-5.000	40.0	35.0	6	–
	Alclad 6061 F	0.250-3.000	–	–	–	–

Welding of 6061 Aluminum Alloy

Al-6061 alloy is easy to weld and connect by various methods. Usually welded with ER4043; For getting the best color matching, ER5356 is recommended.

The following table summarizes common similar metal welded joints made using inertial drive FRW.

Notes:

• Metal Loss: The total shortening of the workpiece during the welding process.
• Total Time: The sum of heating time plus welding time.

Inertia-driven friction welding parameters of two 25 mm (1 in.) diameter rods made of similar metals.
Work Metal	Spindle Speed, Rev/Min	5700
Aluminium Alloy 6061	Axial Force, KN (lbf x 103)	31 (7)
	Flywheel Size, kg·m2 (lb·ft2)	0.13 (3)
	Weld Energy, KJ (ft·lbf x 103)	23 (17)
	Metal Loss, mm (in.)	3.8 (0.15)
	Total Time, s	1

The following table gives parameters used for inertia welding several common dissimilar material combinations.

Note for Axial Force: A force of 22 KN (5000 lbf) is applied during the heating stage of the welding; the force near the end of the weld is subsequently increased to 67 KN (15000 LBF).

Inertia-driven friction welding parameters of two 25 mm (1 in.) diameter rods made of dissimilar metals.
Work Metal	Spindle Speed, Rev/Min	5500
Aluminum 6061 to type 302 stainless	Axial Force, KN (lbf x 103)	22 (5)
		67 (15)
	Flywheel Size, kg·m2 (lb·ft2)	0.16 (3.9)
	Weld Energy, KJ (ft·lbf x 103)	27 (20)
	Metal Loss, mm (in.)	5.1 (0.2)
	Total Time, s	3

Effect of welding conditions on the welding strength of AL-6061 alloy
Base metal alloy and temper	Thickness, mm (in.)	Welding process and conditions	As-welded			Only aged after welding			Postweld solution heat treated and aged
			Tensile strength, MPa (ksi)	0.2%, Yield strength, MPa (ksi)	Elongation in 51 mm (2 in.), ≥%	Tensile strength, MPa (ksi)	0.2%, Yield strength, MPa (ksi)	Elongation in 51 mm (2 in.), ≥%	Tensile strength, MPa (ksi)	0.2%, Yield strength, MPa (ksi)	Elongation in 51 mm (2 in.), ≥%
6061-T6 (4043 Filler)	3.2 (1/8)	DCEN GTAW, 15 mm/s (35 in./min)	248 (36)	165 (24)	6	–	–	–	303 (44)	276 (40)	5
6061-T4 (4043 Filler)	3.2 (1/8)	DCEN GTAW, 8.5 mm/s (20 in./min)	234 (34)	145 (21)	8	283 (41)	179 (26)	3	303 (44)	276 (40)	5
6061-T6 (4043 Filler)	6.4 (1/4)	Automatic GMAW, one pass each side 17 mm/s (40 in./min)	255 (37)	138 (20)	6	–	–	–	296 (43)	276 (40)	5
6061-T4 (4043 Filler)	76 (3)	Automatic GMAW, multipass double-V	172 (25)	90 (13)	10	–	–	–	234 (34)	–	4
6061-T6 (4643 Filler)	76 (3)	Automatic GMAW, multipass double-V	186 (27)	97 (14)	13	–	–	–	310 (45)	276 (40)	4

Typical mechanical properties of gas shielded arc welded butt joints in selected heat-treated heat treatable aluminum alloys.
Base alloy and temper	Filler alloy	As-welded				Postweld solution heat treated and aged
		Tensile strength	0.2% Yield strength, in 50.8 mm (2 in.)	Elongation		Tensile strength	0.2% Yield strength, in 50.8 mm (2 in.)	Elongation
		MPa (ksi)	MPa (ksi)	Tensile, ≥% in 50.8 mm (2 in.)	Free bend, %	MPa (ksi)	MPa (ksi)	Tensile, ≥% in 50.8 mm (2 in.)	Free bend, %
AA-6061-T4	4043	186 (27)	124 (18)	8	16	241 (35) ①	165 (24) ①	3 ①	–
AA-6061-T6	4043	186 (27)	124 (18)	8	16	303 (44) ②	276 (40) ②	5 ②	11 ②
AA-6061-T6	5356	207 (30)	131 (19)	11	25	–	–	–	–

Notes:

• ① Postweld artificially aged only.
• ② For thicknesses greater than 19 mm (3/4 inch), 4643 filler is required.

Heat Treating of Aluminum 6061

Typical Heat Treatments for 6061 Aluminum Alloy Mill Products
Aluminium Alloy	Product	Solution heat treatment		Precipitation heat treatment		Temper designation
		Metal temperature, °C (°F)	Temper designation	Metal temperature, °C (°F)	Approx. time at temperature, h
AA6061	Sheet	530 (985)	T4	160 (320)	18	T6
			T42			T62
	Plate	530 (985)	T4 (tread plate only), T451	160 (320)	18	T6 (tread plate only), T651
			T42	160 (320)	18	T62
	Rolled or Cold finished Wire, Rod & Bar	530 (985)	T4, T3, T4, T4, T451	160 (320), An alternative treatment comprised of 8 hours at 170 (340) also may be used.	18	T6, T89, T913, T94, T651
			T42			T62
	Extruded Rod, Bar, Profiles and Tube	Quenched directly from the extrusion press.	T1	175	8	T51
		530 (985)	T4, T4510, T4511	175	8	T6, T6510, T6511
		530 (985)	T42	175	8	T62
	Structural Profiles	530 (985)	T4	175	8	T6
	Pipe	530 (985)	T4	175	8	T6
	Drawn Pipe	530 (985)	T4	160	18	T6
			T42	160	18	T62
	Die and Hand Forgings	530 (985)	T4	175	8	T6
	Rolled Rings	530 (985)	T4	175	8	T6
			T452	175	8	T652

AA-6061 Annealing

Typical full annealing treatment (O condition): The annealing process is an average process. Heat to 415 °C (775 °F) for 2 to 3 hours, then slowly cool (28 °C/hr) to 260 °C (500 °F). The intermediate annealing for removing cold work should be performed at 343 °C (650 °F). Time and cooling rate are not critical.

6061 Aluminium Aging

6061 aluminium alloy sheets, plates, rolled or cold-rolled wire, rods, bars, and drawn tubing are aged to a metal temperature of 160 °C (320 °F) and maintaining it for 18h. Extruded rods, rods, shapes and tubes; dies and hand forgings, rolled rings are aged to a metal temperature of 175 °C (345 °F) and held for 8 hours.

Al 6061 Alloy Corrosion Resistance

Al 6061 alloy has excellent corrosion resistance to atmospheric conditions and good corrosion resistance to seawater. This alloy also has a good finish and a good reaction to anodic oxidation. However, where appearance is crucial, consider using 6060 or 6063 alloy.

Typical Applications of 6061 Aluminum Alloy

Representative applications of 6061 aluminium alloy include aerospace and electrical fixtures, as well as communications. They are also widely used in automated machinery parts, precision machining, mold manufacturing, electronics and precision instruments, SMT, PC board solder carriers, etc.

• Aerospace: 6061 aluminium alloy can be used to make aircraft skins, fuselage frames, beams, rotors, propellers, fuel tanks, siding and landing gear pillars, as well as rocket forging rings, spacecraft siding, etc.
• Transportation: 6061 aluminium alloy also used for car, subway car, railway passenger car, high-speed passenger car body structural materials, doors and windows, shelves, automotive engine parts, air conditioners, radiators, body panels, wheels and ship materials.
• Packaging: Aluminum alloy 6061 is also used as metal packaging materials in the form of thin plates and foils, made into cans, lids, bottles, barrels, packaging foils, which are widely used in packaging of beverages, food, cosmetics, medicines, cigarettes, industrial products, etc.
• Printing: Mainly used to make PS plates. Aluminum-based PS plates are a new type of material for the printing industry. They are used for automatic plate making and printing.
• Architectural decoration: alloy 6061 is mainly used in building frames, doors and windows, suspended ceilings, metal curtains, perforated metal sheet, decorative surfaces, etc. Such as various architectural doors and windows, aluminum profiles for curtain walls, aluminum curtain wall panels, profiled panels, checkered panels, color coated aluminum panels, etc.
• Electronic home appliances: 6061 also used in various busbars, wiring, conductors, electrical components, refrigerators, air conditioners, cables and other fields.

6061 Aluminium Alloy Equivalent

Aluminum 6061 equivalent to European EN (German DIN EN, British BSI EN, France NF EN), ISO, Japanese JIS and Chinese GB standard (for reference).

Notes: DIN 1725-1 has been replaced by DIN EN 573-3.

AA-6061 Aluminum Equivalent Material

US

European Union

Germany

China

Japan

ISO

Standard

Grade (UNS)

Standard

Grade

Standard

Numerical (Chemical symbols)

Norm

Aluminum name (material number)

Standard

Grade

Standard

Grade

Standard

Grade

AA; ASTM B209; ASTM B211; ASTM B221; ASTM B210; ASTM B308/B308M; ASTM B241/B241M

6061 (UNS A96061)

SAE AMS 4025; SAE AMS 4026; SAE AMS 4027; SAE AMS 4117

6061

EN 573-3

EN AW-6061 (EN AW-AlMg1SiCu)

DIN 1725-1

AlMgSi1Cu (3.3211)

GB/T 3190; GB/T 3880.2

6061

JIS H4000; JIS H4040

6061

ISO 209

AW-6061

Related materials: SAE 5160 Steel, Type 302 Stainless Steel, AISI 904L Stainless Steel, AISI 304 Stainless Steel, SAE 1080 Steel, X5CrNi18-10 (1.4301)