Copper Alloy QBe1.9-TH03
Precip hard
GB QBe1.9
Intermediate aged spring temper where TH04 would be too brittle for the bend radius.
Values for the TH03 condition
Other QBe1.9 tempers and conditions
QBe1.9 is listed in 12 conditions; see the grade overview at QBe1.9.
Compare all 12 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Solution heat treated | Softest condition — pick for deep drawing, stamping and complex forming before customer-side age hardening. | 240 | 480 | 45 | 105 HB | 17 % IACS |
Solution heat treated and cold worked, quarter hard | Light cold work for moderate forming plus a small pre-age strength boost. | 450 | 560 | 28 | 150 HB | 17 % IACS |
Solution heat treated and cold worked, half hard | Balanced strength/formability strip and rod for parts formed with modest bend radii before aging. | 585 | 640 | 15 | 190 HB | 17 % IACS |
three-quarter hard, cold worked | Intermediate step between half and full hard for flat springs needing limited forming. | 640 | 700 | 9 | 15 HRC | 17 % IACS |
Mill hardened, half hard | Mill-hardened strip supplied ready to stamp — no customer aging, dimensionally stable, moderate strength with good formability. | 690 | 830 | 12 | 27 HRC | 20 % IACS |
Solution heat treated and cold worked, full hard | Maximum pre-age cold work — highest strength before aging, used for flat springs and blanked contacts. | 720 | 780 | 5 | 21 HRC | 17 % IACS |
Mill hardened, extra hard | High-strength mill-hardened strip for high-force connector springs where post-form aging is not practical. | 965 | 1,070 | 6 | 34 HRC | 21 % IACS |
TF00Default Solution heat treated and precipitation hardened | Standard peak-aged condition for machined parts, moulds, bushings and non-sparking tools — best strength/ductility balance. | 1,070 | 1,240 | 5 | 39 HRC | 23 % IACS |
TD01 and precipitation hardened | Cold worked 1/4 hard then aged — slightly stronger than AT while retaining useful ductility. | 1,120 | 1,275 | 4 | 40 HRC | 23 % IACS |
TD02 and precipitation hardened | Standard high-strength spring strip condition for connectors and contact fingers. | 1,190 | 1,330 | 4 | 42 HRC | 23 % IACS |
TH03This page three-quarter hard then aged | Intermediate aged spring temper where TH04 would be too brittle for the bend radius. | 1,240 | 1,380 | 3 | 43 HRC | 24 % IACS |
TD04 and precipitation hardened | Maximum strength and hardness of the alloy — flat springs, diaphragms and Bourdon tubes with minimal forming after aging. | 1,240 | 1,380 | 2 | 43 HRC | 23 % IACS |
What is QBe1.9-TH03?
QBe1.9-TH03 is QBe1.9 in the TH03 condition — intermediate aged spring temper where TH04 would be too brittle for the bend radius. QBe1.9-TH03 has a yield strength of 1,240 MPa (180 ksi) and a tensile strength of 1,380 MPa (200 ksi) — stronger than 100% of copper alloy grades. Elongation at break is 3% and the elastic modulus is 128 GPa (18.6 Msi). QBe1.9-TH03 has a density of 8.26 g/cm³ (0.298 lb/in³), lighter than 83% of copper alloy grades. It melts at 865°C (1,589 °F). TF00 is the default condition FabDigit quotes; TH03 is available on request or by drawing note.
Advantages
- High strength — 1,240 MPa (180 ksi), better than 100% of copper alloy grades
- Polishes to a fine finish — 85/100, better than 92% of copper alloy grades
Limitations
- Limited ductility — 3%, worse than 97% of copper alloy grades
- High embodied carbon — 7.5 kg CO₂/kg, worse than 97% of copper alloy grades
- Limited formability — 8/100, worse than 94% of copper alloy grades
- Low fracture toughness — 35 MPa·√m (31.9 ksi·√in), worse than 79% of copper alloy grades
QBe1.9-TH03 properties
Typical room-temperature values for QBe1.9-TH03; 22 are specific to this condition. Other listed values are QBe1.9 reference data and may not represent this condition. Bars are the position among copper alloy grades.
Physical3
QBe1.9-TH03 has a density of 8.26 g/cm³ (0.298 lb/in³), lighter than 83% of copper alloy grades. It melts at 865°C (1,589 °F).
Mechanical16
QBe1.9-TH03 has a yield strength of 1,240 MPa (180 ksi) and a tensile strength of 1,380 MPa (200 ksi) — stronger than 100% of copper alloy grades. Elongation at break is 3% and the elastic modulus is 128 GPa (18.6 Msi).
Thermal6
QBe1.9-TH03 is rated for continuous service to 200°C (392 °F). It conducts heat at 115 W/m·K (66.4 BTU/hr·ft·°F), better than 61% of copper alloy grades. Thermal expansion is 17 µm/m·K (9.44 µin/in·°F).
Electrical3
QBe1.9-TH03 conducts electricity at 24 % IACS, better than 57% of copper alloy grades.
Chemical & Environmental3
Corrosion resistance is good (62/100), worse than 57% of copper alloy grades.
Sustainability4
Producing a kilogram of QBe1.9-TH03 takes about 105 MJ of energy and emits 7.5 kg of CO₂ — more than 97% of copper alloy grades. Typical recycled content is 25%.
Manufacturability8
QBe1.9-TH03's machinability is fair (40/100, better than 57% of copper alloy grades); weldability fair (45/100); formability not recommended (8/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with QBe1.9-TH03
Is QBe1.9 easy to machine?
Machine in TB00/TD tempers where possible; aged material cuts like 40 HRC steel — use carbide, rigid setups, flood coolant and full dust/fume capture for beryllium.
Can QBe1.9 be welded?
Resistance and electron-beam welding are routine; TIG is possible with matched filler and inert shielding, but the weld zone must be re-solution treated and re-aged, and fume extraction is mandatory.
Can QBe1.9 be formed, bent or molded?
Do all deep drawing, bending and coiling in the solution-annealed or cold-worked temper, then age at 315–330 °C for 2–3 h (allow ~0.2 % dimensional contraction); aged stock has very limited formability.
What surface finishes work on QBe1.9?
Not anodizable; degrease and pickle to remove the aging oxide, then nickel, tin or gold plate for contacts, or polish to mirror finish for mould inserts.
QBe1.9 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 |
|---|---|---|
| Beprincipal hardening element | 1.85 – 2.1 | 1.95 |
| Nigrain refiner / aging control | 0.2 – 0.4 | 0.3 |
| Ti | 0.1 – 0.25 | 0.18 |
| Alimpurity limit | ≤ 0.15 | — |
| Feimpurity limit | ≤ 0.15 | — |
| Siimpurity limit | ≤ 0.15 | — |
| Pbimpurity limit | ≤ 0.01 | — |
| Curemainder, total impurities ≤ 0.5 % | balance | — |
QBe1.9-TH03 — frequently asked
What is QBe1.9-TH03 used for?
QBe1.9-TH03 is typically used for precision springs, electrical contacts, molds and non-sparking tools. In short: highest-strength copper alloy; spring and mould-insert grade; requires beryllium dust control.
What is the yield strength of QBe1.9-TH03?
QBe1.9-TH03 has a typical yield strength of 1,240 MPa (180 ksi) and a tensile strength of 1,380 MPa (200 ksi) — stronger than 100% of copper alloy grades. Strength varies by condition: see the 12 listed tempers.
Is QBe1.9-TH03 easy to machine?
Not especially — machinability is rated fair (40/100, better than 57% of copper alloy grades). Machine in TB00/TD tempers where possible; aged material cuts like 40 HRC steel — use carbide, rigid setups, flood coolant and full dust/fume capture for beryllium.
Can QBe1.9-TH03 be welded?
With care — weldability is rated fair (45/100). Resistance and electron-beam welding are routine; TIG is possible with matched filler and inert shielding, but the weld zone must be re-solution treated and re-aged, and fume extraction is mandatory.
What surface finishes work on QBe1.9-TH03?
Not anodizable; degrease and pickle to remove the aging oxide, then nickel, tin or gold plate for contacts, or polish to mirror finish for mould inserts.
Can QBe1.9-TH03 be formed, bent or molded?
Do all deep drawing, bending and coiling in the solution-annealed or cold-worked temper, then age at 315–330 °C for 2–3 h (allow ~0.2 % dimensional contraction); aged stock has very limited formability.
What is the maximum service temperature of QBe1.9-TH03?
QBe1.9-TH03 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 QBe1.9-TF00 and QBe1.9-TB00?
TF00 is the default condition — standard peak-aged condition for machined parts, moulds, bushings and non-sparking tools — best strength/ductility balance. TB00: softest condition — pick for deep drawing, stamping and complex forming before customer-side age hardening. Yield strength is 1,070 MPa in TF00 versus 240 MPa in TB00.
Sources
- C17200 Alloy Datasheet — Copper Development Association (copper.org) (2023)
- Alloy 25 (C17200) Strip and Rod Technical Data — Materion Brush Performance Alloys (2021)
- ASM Handbook Vol.2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
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.