Aluminum 4032 · temper
Aluminum 4032-T651
Properties of the T651 condition, compared with the other 4032 tempers.
Pick when dimensional stability after heavy machining matters (residual stresses removed); mechanicals essentially those of T6.
What is 4032-T651?
4032-T651 is 4032 in the T651 temper — pick when dimensional stability after heavy machining matters (residual stresses removed); mechanicals essentially those of T6. 4032-T651 has a yield strength of 315 MPa (45.7 ksi) and a tensile strength of 380 MPa (55.1 ksi) — stronger than 78% of aluminum grades. Elongation at break is 8% and the elastic modulus is 79 GPa (11.5 Msi). 4032-T651 has a density of 2.69 g/cm³ (0.097 lb/in³), lighter than 69% of aluminum grades. It melts at 532°C (990 °F).
Advantages
- High service temperature — 175°C (347 °F), better than 83% of aluminum grades
- High strength — 315 MPa (45.7 ksi), better than 78% of aluminum grades
Limitations
- Hard to polish — 45/100, worse than 76% of aluminum grades
4032-T651 properties
Typical room-temperature values for 4032-T651 — 10 properties are specific to this condition; the rest are grade-level values shared by every 4032 temper. Each bar shows where the value sits among the aluminum grades in FabDigit's library — further right is higher.
Physical3
4032-T651 has a density of 2.69 g/cm³ (0.097 lb/in³), lighter than 69% of aluminum grades. It melts at 532°C (990 °F).
Mechanical12
4032-T651 has a yield strength of 315 MPa (45.7 ksi) and a tensile strength of 380 MPa (55.1 ksi) — stronger than 78% of aluminum grades. Elongation at break is 8% and the elastic modulus is 79 GPa (11.5 Msi).
Thermal6
4032-T651 is rated for continuous service to 175°C (347 °F). It conducts heat at 141 W/m·K (81.5 BTU/hr·ft·°F), better than 50% of aluminum grades. Thermal expansion is 19.4 µm/m·K (10.8 µin/in·°F).
Electrical3
4032-T651 conducts electricity at 40 % IACS, better than 72% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is fair (45/100), worse than 62% of aluminum grades.
Sustainability4
Producing a kilogram of 4032-T651 takes about 205 MJ of energy and emits 12.5 kg of CO₂ — more than 75% of aluminum grades. Typical recycled content is 25%.
Manufacturability7
4032-T651's machinability is good (58/100, worse than 53% of aluminum grades); weldability fair (40/100); formability poor (20/100).
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other 4032 tempers and conditions
4032 is also supplied in 2 other conditions. The full side-by-side table is on the 4032 overview.
- T6Standard service condition for forged pistons and wear parts — peak strength plus best hot hardness retention.315 MPa yield · 120 HB
- T651Pick when dimensional stability after heavy machining matters (residual stresses removed); mechanicals essentially those of T6.315 MPa yield · 120 HB
- OSoftest condition, used for maximum machining/upsetting freedom before solution treatment; not a service temper.110 MPa yield · 65 HB
Working with 4032-T651
Is 4032 easy to machine?
Machines to fine chips and good finish but the primary Si is very abrasive — use PCD or polished carbide, high speed, low feed and flood coolant.
Can 4032 be welded?
Fusion welding is limited (Cu+Mg raise crack sensitivity); if required use 4043/4145 filler and post-weld solution + age, otherwise join mechanically.
Can 4032 be formed, bent or molded?
Hot forging/extrusion at roughly 400–470 °C is the intended route; cold forming and bending are poor — do not rely on cold work in T6.
What surface finishes work on 4032?
Hard (type III) anodize for piston skirts and wear faces; decorative anodize turns dark grey, and electroless nickel or Fe-phosphate/graphite coatings are also common.
4032 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.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| Siprimary Si gives wear resistance and low CTE | 11 – 13.5 | 12.2 |
| Cu | 0.5 – 1.3 | 0.9 |
| MgMg2Si precipitation strengthening | 0.8 – 1.3 | 1 |
| Nielevated-temperature strength | 0.5 – 1.3 | 0.9 |
| Fe | ≤ 1 | — |
| Cr | ≤ 0.1 | — |
| Zn | ≤ 0.25 | — |
| Others (each)total 0.15 max | ≤ 0.05 | — |
| Al | balance | — |
4032-T651 — frequently asked
What is 4032-T651 used for?
4032-T651 is typically used for forged engine pistons, reciprocating compressor pistons, cylinder liners and wear sleeves, motorsport and motorcycle piston blanks, pump wear components and machined parts needing low thermal expansion. In short: forged piston alloy; high wear and heat resistance.
What is the yield strength of 4032-T651?
4032-T651 has a typical yield strength of 315 MPa (45.7 ksi) and a tensile strength of 380 MPa (55.1 ksi) — stronger than 78% of aluminum grades. Strength varies by condition: see the 3 listed tempers.
Is 4032-T651 easy to machine?
Reasonably — machinability is rated good (58/100, worse than 53% of aluminum grades). Machines to fine chips and good finish but the primary Si is very abrasive — use PCD or polished carbide, high speed, low feed and flood coolant.
Can 4032-T651 be welded?
With care — weldability is rated fair (40/100). Fusion welding is limited (Cu+Mg raise crack sensitivity); if required use 4043/4145 filler and post-weld solution + age, otherwise join mechanically.
What surface finishes work on 4032-T651?
Hard (type III) anodize for piston skirts and wear faces; decorative anodize turns dark grey, and electroless nickel or Fe-phosphate/graphite coatings are also common.
Can 4032-T651 be formed, bent or molded?
Hot forging/extrusion at roughly 400–470 °C is the intended route; cold forming and bending are poor — do not rely on cold work in T6.
What is the maximum service temperature of 4032-T651?
4032-T651 is rated for continuous use to about 175°C (347 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Can FabDigit make parts in 4032-T651?
Yes — 4032-T651 is available for CNC machining and sheet metal with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- International Alloy Designations and Chemical Composition Limits for Wrought Aluminum (Teal Sheets) — The Aluminum Association (2018)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- EN 573-3 / EN 586 wrought aluminium alloy designations and forgings — CEN (2019)
- Aluminum alloy 4032 property datasheets — MatWeb / MMPDS typical data (2023)
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.