Gr9 (TA18, Ti-3Al-2.5V)

1. Excellent cold working formability (core advantage): Gr9 is one of the titanium alloys with the best cold working performance, capable of undergoing cold drawing, cold rolling, cold bending, cold heading, and other processes. It far outperforms Gr5 (TC4), and its strength can be further enhanced after cold working.
2. Good strength-ductility match: Tensile strength ≥ 620 MPa (annealed condition), elongation ≥ 15%. Its strength is significantly higher than that of industrial pure titanium (Gr2) while maintaining excellent ductility.
3. Superior corrosion resistance: Its corrosion resistance is comparable to that of industrial pure titanium (Gr2), and it performs excellently in seawater, chloride environments, and most acidic and alkaline media.
4. Good welding performance: It has excellent weldability, requiring no complex preheating or post-weld heat treatment. The properties of the welded joint are close to those of the base material.
5. Good hot working performance: It can undergo hot forming processes such as forging, hot rolling, and hot extrusion within the temperature range of 800-1000°C.
6. Compliance with multiple international standards: ASTM B348, ASTM B863, AMS 4943 / AMS 4944, GB/T 3625, etc.

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The excellent cold working performance of Gr9 mainly stems from its lower alloy element content and near-alpha microstructure:
1. Lower deformation resistance: The content of Al (3%) and V (2.5%) in Gr9 is much lower than that in Gr5 (Al 6%, V 4%), resulting in lower solid solution strengthening and thus smaller cold deformation resistance.
2. Better ductility: The elongation of Gr9 in the annealed state is ≥ 15%, which is better than Gr5's ≥ 10%. This allows for a larger amount of cold deformation without cracking.
3. Slower work hardening rate: Gr9 has a lower work hardening rate than Gr5, enabling greater deformation in a single cold working operation (cold-drawn tubes can reach 15-30% reduction). This reduces the number of intermediate annealing steps and significantly lowers manufacturing costs.
4. Typical case: Gr9 is the global mainstream choice for aerospace hydraulic precision tubing (outer diameter 2-50mm) and bicycle frame tubing. In contrast, Gr5, due to its poorer cold working performance, is typically produced using hot extrusion or hot rolling methods for tubing.

Gr9 has excellent welding properties and is one of the best grades of titanium alloy in terms of weldability:
1. Recommended welding methods: TIG (Tungsten Inert Gas Welding), MIG (Metal Inert Gas Welding), Plasma Welding, Electron Beam Welding, Laser Welding, and Resistance Welding.
2. Pre-welding preparation: The welding area must be strictly cleaned to remove oil, scale, and moisture.
3. Protective gas: High-purity argon gas (≥ 99.99%) should be used for welding and backside protection to prevent high-temperature oxidation contamination.
4. Post-welding treatment: Post-weld heat treatment is generally not required. If extremely high dimensional stability is required, post-weld stress-relief annealing (approximately 500-600°C, air-cooled) can be considered.
5. Filler metal: It is recommended to use Gr9 filler wire of the same material or Gr5 (TC4) filler wire to ensure weld performance compatibility.

1. Continuous operating temperature (primarily for strength and oxidation resistance): It is recommended to be ≤ 350°C, where good mechanical properties and corrosion resistance can be maintained. Short-term exposure can reach up to 400-450°C, but strength degradation should be considered.
2. Low-temperature properties: Gr9 exhibits excellent ductility and toughness at low temperatures (down to -196°C), similar to TA7, making it suitable for applications such as low-temperature piping and low-temperature storage tanks.
3. Application examples: Gr9 is an internationally recognized grade for aerospace hydraulic tubing (AMS 4943 / AMS 4944). The operating temperature range of aircraft hydraulic systems is typically from -55°C to 135°C, and Gr9 fully meets the requirements of this temperature range.

The most common application form of Gr9 is precision cold-drawn tubing, which is its largest and most mature application market:
1. Tubing (Maximum Application): Aerospace hydraulic tubing (outer diameter 2-50mm, wall thickness 0.5-3mm), bicycle frame tubes, heat exchanger tubes, chemical process piping. Gr9 is the material specified for aerospace hydraulic tubing in AMS 4943 / AMS 4944 standards.
2. Wire/Rod: Medical guidewires, welding filler wires, springs, fasteners.
3. Strip/Sheet: Precision stamped parts, corrugated tubes, gaskets.
4. Bar: Fasteners, structural components, bicycle parts.
5. Plate: Aerospace skin, heat exchanger plates, chemical lining plates.
For quotations on specific specifications, material test reports, or technical parameter sheets, please contact our sales engineers. We support customizing dimensions, heat treatment conditions, and surface treatments as per requirements, and provide a full set of internationally certified documents.