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Aluminum Sintered 6061 AT4-T4-I

Precip hard

also MPIF 6061

AT4-T4-I = aT4-6061 Type I

Best strength/ductility compromise for parts that are still sized, staked or riveted after heat treatment.

High cost $$$$

Values for the AT4-T4-I condition

Other Sintered 6061 tempers and conditions

Sintered 6061 is listed in 6 conditions; see the grade overview at Sintered 6061.

Compare all 6 conditionsHide
Condition · open for datasheetBest forYield MPaTensile MPaElong. %HardnessConductivity
AT1-6061 Type I
Lowest-cost condition: softest, most ductile and easiest to size or coin after sintering.62117440 HB38 % IACS
AT1-6061 Type II
Same soft T1 state but higher pressed density for better strength, stiffness and surface sealing.83145648 HB42 % IACS
AT4-T4-IThis page
AT4-6061 Type I
Best strength/ductility compromise for parts that are still sized, staked or riveted after heat treatment.961483.555 HB34 % IACS
AT4-6061 Type II
Higher-density T4 for load-bearing parts that must still tolerate some post-sinter deformation.110179562 HB38 % IACS
AT6-T6-IDefault
AT6-6061 Type I
Standard stocked condition: maximum strength and hardness for single-press/single-sinter PM 6061 parts.193200170 HB38 % IACS
AT6-6061 Type II
Highest strength and stiffness variant of sintered 6061; specify for the most loaded PM aluminium parts.235245280 HB42 % IACS

What is Sintered 6061 AT4-T4-I?

Sintered 6061 AT4-T4-I is Sintered 6061 in the AT4-T4-I condition — best strength/ductility compromise for parts that are still sized, staked or riveted after heat treatment. Sintered 6061 AT4-T4-I has a yield strength of 96 MPa (13.9 ksi) and a tensile strength of 148 MPa (21.5 ksi) — weaker than 85% of aluminum grades. Elongation at break is 3.5% and the elastic modulus is 60 GPa (8.7 Msi). Sintered 6061 AT4-T4-I has a density of 2.55 g/cm³ (0.0921 lb/in³), lighter than 99% of aluminum grades. It melts at 582°C (1,080 °F). AT6-T6-I is the default condition FabDigit quotes; AT4-T4-I is available on request or by drawing note.

Limitations

  • Low stiffness — 60 GPa (8.7 Msi), worse than 100% of aluminum grades
  • Hard to polish — 40/100, worse than 91% of aluminum grades
  • Low strength — 96 MPa (13.9 ksi), worse than 85% of aluminum grades
  • Limited service temperature — 120°C (248 °F), worse than 79% of aluminum grades
  • Limited ductility — 3.5%, worse than 76% of aluminum grades

Sintered 6061 AT4-T4-I properties

Typical room-temperature values for Sintered 6061 AT4-T4-I; 35 are specific to this condition. Other listed values are Sintered 6061 reference data and may not represent this condition. Bars are the position among aluminum grades.

Physical3

Sintered 6061 AT4-T4-I has a density of 2.55 g/cm³ (0.0921 lb/in³), lighter than 99% of aluminum grades. It melts at 582°C (1,080 °F).

Density2.55 g/cm³0.09 lb/in³
Melting Point (Solidus)582°C1,080 °F
Liquidus Temperature652°C1,206 °F

Mechanical13

Sintered 6061 AT4-T4-I has a yield strength of 96 MPa (13.9 ksi) and a tensile strength of 148 MPa (21.5 ksi) — weaker than 85% of aluminum grades. Elongation at break is 3.5% and the elastic modulus is 60 GPa (8.7 Msi).

Elastic (Young's) Modulus60 GPa8.7 Msi
Shear Modulus22 GPa3.2 Msi
Bulk Modulus58 GPa8.4 Msi
Poisson's Ratio0.31
Tensile Strength (Ultimate)148 MPa21.5 ksi
Yield Strength (0.2% offset)96 MPa13.9 ksi
Elongation at Break3.5%
Compressive Strength210 MPa30.5 ksi
Shear Strength100 MPa14.5 ksi
Fatigue Strength (Endurance Limit)45 MPa6.5 ksi
Fracture Toughness (K_IC)18 MPa·√m16.4 ksi·√in
Charpy V-Notch Impact (RT)6 J4.4 ft·lbf
Hardness, Brinell55 HB

Thermal6

Sintered 6061 AT4-T4-I is rated for continuous service to 120°C (248 °F). It conducts heat at 130 W/m·K (75.1 BTU/hr·ft·°F), worse than 65% of aluminum grades. Thermal expansion is 23.4 µm/m·K (13 µin/in·°F).

Thermal Conductivity130 W/m·K75.1 BTU/hr·ft·°F
Specific Heat Capacity896 J/kg·K0.21 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)23.4 µm/m·K13 µin/in·°F
Latent Heat of Fusion395 J/g170 BTU/lb
Max Service Temperature (continuous)120°C248 °F
Min Service Temperature-196°C-321 °F

Electrical3

Sintered 6061 AT4-T4-I conducts electricity at 34 % IACS, worse than 52% of aluminum grades.

Electrical Conductivity34 % IACS
Electrical Resistivity5.1×10⁻⁸ Ω·m2.01 µΩ·in
Magnetic Responsenon-magnetic

Chemical & Environmental3

Corrosion resistance is good (55/100), worse than 51% of aluminum grades.

Galvanic Potential (seawater, vs SCE)-0.78 V
Corrosion ResistanceGood55/100
Chemical Resistance SummaryQuench salts and porosity must be flushed after solution treatment; otherwise resistance parallels wrought 6061-T4 with reduced pitting margin.

Sustainability4

Producing a kilogram of Sintered 6061 AT4-T4-I takes about 220 MJ of energy and emits 13.5 kg of CO₂ — more than 95% of aluminum grades. Typical recycled content is 25%.

Embodied Energy (primary production)220 MJ/kg94,583 BTU/lb
Embodied Carbon (primary production)13.5 kg CO₂/kg
Embodied Water1,150 L/kg138 gal/lb
Typical Recycled Content25%

Manufacturability7

Sintered 6061 AT4-T4-I's machinability is very good (70/100, better than 72% of aluminum grades); weldability fair (35/100); formability fair (35/100).

MachinabilityVery good70/100
Machinability Rating (AISI 1212 = 100 %)160%
WeldabilityFair35/100
Formability (cold)Fair35/100
Brazeability / SolderabilityFair40/100
PolishabilityFair40/100
Anodizing Responsefair – acceptable for clear/chromate-free seals; porous surface bleeds electrolyte and mottles dyed finishes

Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.

Working with Sintered 6061 AT4-T4-I

Is Sintered 6061 easy to machine?

Machines like soft wrought 6061 but pores break chips and can smear — use sharp polished-flute carbide, high speed, light feeds and flood coolant; deburr and blow out pores before assembly.

Can Sintered 6061 be welded?

Fusion welding is generally avoided: trapped gas and lubricant residue cause weld porosity; join by adhesive bonding, mechanical fastening, staking or brazing of impregnated parts.

Can Sintered 6061 be formed, bent or molded?

Formed by die compaction of admixed 6061 powder (typically 200–500 MPa), delubrication and nitrogen sintering near 595–620 °C, then optional repressing/sizing (Type II) and T4/T6 heat treatment; net shrinkage/growth must be built into tooling.

What surface finishes work on Sintered 6061?

Anodizing gives a duller, mottled film unless resin or steam impregnation seals the porosity; chromate/trivalent conversion coating, e-coat or resin impregnation followed by paint are the usual routes, and polishing is limited by open pores.

Sintered 6061 chemical composition (wt %)

Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.

ElementSpec limit (wt %)Nominal
Mg0.8 – 1.21
Si0.4 – 0.80.6
Cu0.15 – 0.40.25
Cr0.04 – 0.350.2
Fe≤ 0.70.2
Mn≤ 0.150.05
Zn≤ 0.250.05
Ti≤ 0.150.05
Cresidual from admixed lubricant (PM-specific, burn-off dependent)≤ 0.30.1
Albalance; each other element ≤0.05, total ≤0.15balance—

Sintered 6061 AT4-T4-I — frequently asked

What is Sintered 6061 AT4-T4-I used for?

Sintered 6061 AT4-T4-I is typically used for P/M structural brackets, small housings, automotive components and consumer electronics parts. In short: corrosion-resistant P/M aluminum; heat-treatable to T6; near-net shape cost saving.

What is the yield strength of Sintered 6061 AT4-T4-I?

Sintered 6061 AT4-T4-I has a typical yield strength of 96 MPa (13.9 ksi) and a tensile strength of 148 MPa (21.5 ksi) — weaker than 85% of aluminum grades. Strength varies by condition: see the 6 listed tempers.

Is Sintered 6061 AT4-T4-I easy to machine?

Yes — machinability is rated very good (70/100, better than 72% of aluminum grades). Machines like soft wrought 6061 but pores break chips and can smear — use sharp polished-flute carbide, high speed, light feeds and flood coolant; deburr and blow out pores before assembly.

Can Sintered 6061 AT4-T4-I be welded?

With care — weldability is rated fair (35/100). Fusion welding is generally avoided: trapped gas and lubricant residue cause weld porosity; join by adhesive bonding, mechanical fastening, staking or brazing of impregnated parts.

What surface finishes work on Sintered 6061 AT4-T4-I?

Anodizing gives a duller, mottled film unless resin or steam impregnation seals the porosity; chromate/trivalent conversion coating, e-coat or resin impregnation followed by paint are the usual routes, and polishing is limited by open pores.

Can Sintered 6061 AT4-T4-I be formed, bent or molded?

Formed by die compaction of admixed 6061 powder (typically 200–500 MPa), delubrication and nitrogen sintering near 595–620 °C, then optional repressing/sizing (Type II) and T4/T6 heat treatment; net shrinkage/growth must be built into tooling.

What is the maximum service temperature of Sintered 6061 AT4-T4-I?

Sintered 6061 AT4-T4-I is rated for continuous use to about 120°C (248 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.

Sources

  1. MPIF Standard 35 — Materials Standards for PM Structural Parts (Aluminum P/M alloys) — Metal Powder Industries Federation (2016)
  2. ASM Handbook Vol. 7 — Powder Metallurgy (Aluminium PM alloys) — ASM International (2015)
  3. ASM Handbook Vol. 2 — Properties of Nonferrous Alloys (6061) — ASM International (1990)
  4. Aluminum Association Teal Sheets — Alloy 6061 chemical composition limits — The Aluminum Association (2018)
  5. Sintered aluminium P/M alloy property tables (density-dependent strength data) — FabDigit compilation (2026)
  6. Aluminium alloy powder spot price levels (SMM / 1688 wholesale listings) (2026)

Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.