Aluminum 333.0-T7
Temper
AA 333.0 · UNS A03330 · BS LM24 · also SC94A
T7 = solution heat treated and overaged (stabilized)
Slightly lower strength than T6 but best dimensional stability and retained properties at elevated temperature.
Values for the T7 condition
Other 333.0 tempers and conditions
333.0 is listed in 4 conditions; see the grade overview at 333.0.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
FDefault As fabricated | Lowest cost condition — pick when moderate strength and best as-cast dimensional stability at low temperature service are enough. | 131 | 234 | 2 | 90 HB | 26 % IACS |
Cooled from hot working and artificially aged | Cheap strength/hardness boost and dimensional stabilizing without solution treatment distortion — good for machined housings. | 172 | 234 | 1 | 100 HB | 29 % IACS |
T7This page Solution heat treated and overaged (stabilized) | Slightly lower strength than T6 but best dimensional stability and retained properties at elevated temperature. | 193 | 255 | 2 | 90 HB | 29 % IACS |
Solution heat treated and artificially aged | Highest strength and hardness of the grade — choose for load-bearing and wear-critical automotive castings. | 207 | 289 | 1.5 | 105 HB | 26 % IACS |
What is 333.0-T7?
333.0-T7 is 333.0 in the T7 temper — slightly lower strength than T6 but best dimensional stability and retained properties at elevated temperature. 333.0-T7 has a yield strength of 193 MPa (28 ksi) and a tensile strength of 255 MPa (37 ksi) — weaker than 51% of aluminum grades. Elongation at break is 2% and the elastic modulus is 72 GPa (10.4 Msi). 333.0-T7 has a density of 2.77 g/cm³ (0.1 lb/in³), heavier than 71% of aluminum grades. It melts at 521°C (970 °F). F is the default condition FabDigit quotes; T7 is available on request or by drawing note.
Advantages
- High service temperature — 200°C (392 °F), better than 90% of aluminum grades
- Easy to machine — 72/100, better than 80% of aluminum grades
Limitations
- Hard to polish — 40/100, worse than 91% of aluminum grades
- Limited formability — 8/100, worse than 88% of aluminum grades
- Limited ductility — 2%, worse than 87% of aluminum grades
- Poor heat conductor — 113 W/m·K (65.3 BTU/hr·ft·°F), worse than 86% of aluminum grades
- Low electrical conductivity — 29 % IACS, worse than 78% of aluminum grades
333.0-T7 properties
Typical room-temperature values for 333.0-T7; 13 are specific to this condition. Other listed values are 333.0 reference data and may not represent this condition. Bars are the position among aluminum grades.
Physical3
333.0-T7 has a density of 2.77 g/cm³ (0.1 lb/in³), heavier than 71% of aluminum grades. It melts at 521°C (970 °F).
Mechanical13
333.0-T7 has a yield strength of 193 MPa (28 ksi) and a tensile strength of 255 MPa (37 ksi) — weaker than 51% of aluminum grades. Elongation at break is 2% and the elastic modulus is 72 GPa (10.4 Msi).
Thermal6
333.0-T7 is rated for continuous service to 200°C (392 °F). It conducts heat at 113 W/m·K (65.3 BTU/hr·ft·°F), worse than 86% of aluminum grades. Thermal expansion is 20.5 µm/m·K (11.4 µin/in·°F).
Electrical3
333.0-T7 conducts electricity at 29 % IACS, worse than 78% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is fair (45/100), worse than 62% of aluminum grades.
Sustainability4
Producing a kilogram of 333.0-T7 takes about 200 MJ of energy and emits 12 kg of CO₂ — less than 60% of aluminum grades. Typical recycled content is 70%.
Manufacturability8
333.0-T7's machinability is very good (72/100, better than 80% of aluminum grades); weldability fair (35/100); formability not recommended (8/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 333.0-T7
Is 333.0 easy to machine?
Machines well with sharp PCD or carbide tooling and flood coolant; eutectic/primary Si is abrasive, so use PCD for volume work.
Can 333.0 be welded?
Poor fusion weldability — high Cu makes it hot-crack prone; repair with 4145/4047 filler and preheat, or use mechanical fastening.
Can 333.0 be formed, bent or molded?
Permanent-mold (gravity die) casting alloy with excellent fluidity and pressure tightness; not cold-formable, avoid thin unfed sections.
What surface finishes work on 333.0?
Anodizing gives only a dark grey cosmetic film; prefer chromate/phosphate conversion coating plus paint or powder coat, or hard anodize for wear.
333.0 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 |
|---|---|---|
| Si | 8 – 10 | 9 |
| Cu | 3 – 4 | 3.5 |
| Mgprovides response to T5/T6 aging | 0.05 – 0.5 | 0.25 |
| Fe | ≤ 1 | 0.7 |
| Mn | ≤ 0.5 | 0.3 |
| Zn | ≤ 1 | 0.3 |
| Ni | ≤ 0.5 | 0.1 |
| Ti | ≤ 0.25 | 0.1 |
| Others (each)each | ≤ 0.05 | — |
| Others (total)total | ≤ 0.35 | — |
| Al | balance | — |
333.0-T7 — frequently asked
What is 333.0-T7 used for?
333.0-T7 is typically used for gear housings, engine brackets and pump bodies. In short: versatile Al-Si-Cu die alloy; good machinability and pressure tightness; balanced strength and wear.
What is the yield strength of 333.0-T7?
333.0-T7 has a typical yield strength of 193 MPa (28 ksi) and a tensile strength of 255 MPa (37 ksi) — weaker than 51% of aluminum grades. Strength varies by condition: see the 4 listed tempers.
Is 333.0-T7 easy to machine?
Yes — machinability is rated very good (72/100, better than 80% of aluminum grades). Machines well with sharp PCD or carbide tooling and flood coolant; eutectic/primary Si is abrasive, so use PCD for volume work.
Can 333.0-T7 be welded?
With care — weldability is rated fair (35/100). Poor fusion weldability — high Cu makes it hot-crack prone; repair with 4145/4047 filler and preheat, or use mechanical fastening.
What surface finishes work on 333.0-T7?
Anodizing gives only a dark grey cosmetic film; prefer chromate/phosphate conversion coating plus paint or powder coat, or hard anodize for wear.
Can 333.0-T7 be formed, bent or molded?
Permanent-mold (gravity die) casting alloy with excellent fluidity and pressure tightness; not cold-formable, avoid thin unfed sections.
What is the maximum service temperature of 333.0-T7?
333.0-T7 is rated for continuous use to about 200°C (392 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 333.0-F and 333.0-T6?
F is the default condition — lowest cost condition — pick when moderate strength and best as-cast dimensional stability at low temperature service are enough. T6: highest strength and hardness of the grade — choose for load-bearing and wear-critical automotive castings. Yield strength is 131 MPa in F versus 207 MPa in T6.
Sources
- ANSI H35.1 / Registration Record of Aluminum Association Alloy Designations (Teal Sheets) — The Aluminum Association (2015)
- ASTM B108 — Aluminum-Alloy Permanent Mold Castings — ASTM International (2019)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials — ASM International (1990)
- ASM Specialty Handbook: Aluminum and Aluminum Alloys — ASM International (1993)
- BS 1490 LM24 (comparable Al-Si8Cu3Fe casting alloy) — BSI (1988)
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.