Titanium and Titanium Alloy Bars
Scope This document specifies the classification and marking, technical requirements, test methods, inspection rules, marking, packaging, transportation, storage, accompanying documents, and order content for titanium and titanium legering bars. This document is applicable to round and rectangular bars of titanium and titanium alloys produced by forging and rolling.
Normative References The contents of the following documents constitute essential clauses of this document through normative references in the text. For dated references, only the version corresponding to that date applies to this document. For undated references, the latest version (including all amendments) applies to this document.
- GB/T 228.1-2021: Metallic Materials—Tensile Testing—Part 1: Method of Test at Room Temperature
- GB/T 228.2: Metallic Materials—Tensile Testing—Part 2: Method of Test at Elevated Temperature
- GB/T 2039: Metallic Materials—Uniaxial Tensile Creep Testing Method
- GB/T 3620.1: Designation and Chemical Composition of Titanium and Titanium Alloys
- GB/T 3620.2: Chemical Composition Permissible Variations for Titanium and Titanium Alloy Processed Products
- GB/T 4698 (All Parts): Methods for Chemical Analysis of Spons Titaan, Titanium, and Titanium Alloys
- GB/T 5168: Methods for Macro and Microstructural Examination of Titanium and Titanium Alloys
- GB/T 5193: Ultrasonic Testing Methods for Titanium and Titanium Alloy Processed Products
- GB/T 6611: Terminology and Metallographic Atlas for Titanium and Titanium Alloys
- GB/T 8180: Packaging, Marking, Transportation, and Storage of Titanium and Titanium Alloy Processed Products
- GB/T 23604: Sampling Methods for Mechanical Property Tests of Titanium and Titanium Alloy Products
- GB/T 23605: Determination Method for Transformation Temperature of Titanium Alloys
- GB/T 34647: Codes for Conditions of Titanium and Titanium Alloy Products
- GB/T 38982: Methods for Dimension Inspection of Titanium and Titanium Alloy Processed Products
- GB/T 39799: Dimensions, Shapes, Weights, and Permissible Variations for Titanium and Titanium Alloy Bars and Wires
- YS/T 1262: Methods for Chemical Analysis of Sponge Titanium, Titanium, and Titanium Alloys—Determination of Multi-element Content by Inductively Coupled Plasma Atomic Emission Spectrometry
Terms and Definitions The terms and definitions defined in GB/T 6611, GB/T 34647, and GB/T 38982 are applicable to this document.
4 Classification and Marking
4.1 Product Classification The grades, conditions, and specifications of the bar products should comply with the provisions in Table 1.
Table 1.
| Cijfer | Condition | Diameter or Section Thickness (mm) | Length (mm) |
|---|---|---|---|
| TA1 | Hot Worked (R) | 7 – 100 | 300 – 6000 |
| TA2 | Cold Worked (Y) | 7 – 100 | 300 – 5000 |
| TA3 | Annealed (M) | 7 – 100 | 300 – 6000 |
| TA1G | Hot Worked (R), Cold Worked (Y) | 7 – 100 | 300 – 6000 |
| TA2G | Hot Worked (R), Cold Worked (Y) | 7 – 100 | 300 – 6000 |
| TA3G | Hot Worked (R), Cold Worked (Y) | 7 – 100 | 300 – 6000 |
| TA4G | Hot Worked (R), Cold Worked (Y) | 7 – 100 | 300 – 6000 |
| TA5 | Hot Worked (R), Cold Worked (Y) | 7 – 100 | 300 – 6000 |
| TA6 | Hot Worked (R), Cold Worked (Y) | 7 – 100 | 300 – 6000 |
| TA7 | Hot Worked (R), Cold Worked (Y) | 7 – 100 | 300 – 6000 |
| TA9 | Hot Worked (R), Cold Worked (Y) | 7 – 100 | 300 – 6000 |
| TA10 | Hot Worked (R), Cold Worked (Y) | 7 – 100 | 300 – 6000 |
| TA13 | Hot Worked (R), Cold Worked (Y) | 7 – 100 | 300 – 6000 |
| TA15 | Hot Worked (R), Cold Worked (Y) | 7 – 100 | 300 – 6000 |
| TA18 | Hot Worked (R), Cold Worked (Y) | 7 – 100 | 300 – 6000 |
| TA19 | Hot Worked (R), Cold Worked (Y) | 7 – 100 | 300 – 6000 |
| TB2 | Hot Worked (R), Cold Worked (Y) | 7 – 100 | 300 – 6000 |
| TB6 | Hot Worked (R), Cold Worked (Y) | 7 – 100 | 300 – 6000 |
| TC1 | Hot Worked (R), Cold Worked (Y) | 7 – 100 | 300 – 6000 |
| TC2 | Hot Worked (R), Cold Worked (Y) | 7 – 100 | 300 – 6000 |
| TC3 | Hot Worked (R), Cold Worked (Y) | 7 – 100 | 300 – 6000 |
| TC4 | Hot Worked (R), Cold Worked (Y) | 7 – 100 | 300 – 6000 |
| TC4EL1 | Hot Worked (R), Cold Worked (Y) | 7 – 100 | 300 – 6000 |
| TC6 | Annealed (M) (Standard Annealing) | 7 – 100 | 300 – 6000 |
| TC9 | Hot Worked (R), Cold Worked (Y) | 7 – 100 | 300 – 6000 |
| TC10 | Hot Worked (R), Cold Worked (Y) | 7 – 100 | 300 – 6000 |
| TC11 | Hot Worked (R), Cold Worked (Y) | 7 – 100 | 300 – 6000 |
| TC12 | Hot Worked (R), Cold Worked (Y) | 7 – 100 | 300 – 6000 |
| TC17 | Hot Worked (R), Cold Worked (Y) | 7 – 100 | 300 – 6000 |
| TC18 | Hot Worked (R), Cold Worked (Y) | 7 – 100 | 300 – 6000 |
| TC21 | Hot Worked (R), Cold Worked (Y) | 7 – 100 | 300 – 6000 |
| TC25 | Hot Worked (R), Cold Worked (Y) | 7 – 100 | 300 – 6000 |
Note:
- TA19 and TC9 titanium alloy bars are supplied in hot-worked (R) and cold-worked (Y) conditions.
- The annealed (M) condition for TC6 titanium alloy bars refers to standard annealing.
4.2 Product Marking
The product marking should be represented in the sequence of product name, grade, condition, specification, and document number.
Example 1: For a round bar made of TA2 grade, in an annealed condition, with a diameter of 100mm and a length of 3000mm to 4000mm, the marking would be: Bar TA2M 100 × (3000~4000) GB/T 2965-2023
Example 2: For a square bar made of TC4 grade, in a hot worked condition, with a section thickness of 90mm and a length of 2000mm, the marking would be: Bar TC4R 90 × 2000 GB/T 2965-2023
Example 3: For a round bar made of TC4 grade, in a hot worked condition, with a diameter of 80mm and a length of 3000mm, the marking would be: Bar TC4R 80 × 3000 GB/T 2965-2023
5 Technical Requirements
5.1 Chemical Composition 5.1.1 The chemical composition of the bars should comply with the provisions of GB/T 3620.1. 5.1.2 When the purchaser takes samples from the product for chemical composition reinspection, the permissible variations in chemical composition should comply with the provisions of GB/T 3620.2.
5.2 Dimensions and Permissible Variations The dimensions and permissible variations of the bars should comply with the provisions of GB/T 39799.
5.3 Mechanical Properties 5.3.1 The mechanical properties of the bars should be tested on specimens after heat treatment. The recommended heat treatment regimes for the specimens are given in Appendix A. 5.3.2 The room temperature tensile properties of the bars should comply with the provisions of Table 2. When required by the purchaser and stated in the order, the high-temperature mechanical properties of certain grades of bars should comply with the provisions of Table 3.
Table 2 Room Temperature Tensile Properties
| Cijfer | Tensile Strength (R<sub>m</sub>) (MPa) | Yield Strength (R<sub>p0.2</sub>) (MPa) | Elongation after Fracture (A) (%) | Reduction of Area (Z) (%) | Remarks |
|---|---|---|---|---|---|
| TA1 | 370 | 250 | 20 | 30 | |
| TA2 | 440 | 320 | 18 | 30 | |
| TA3 | 540 | 410 | 15 | 25 |
| Cijfer | Tensile Strength (R<sub>m</sub>) (MPa) | Yield Strength (R<sub>p0.2</sub>) (MPa) | Elongation after Fracture (A) (%) | Reduction of Area (Z) (%) | Remarks |
|---|---|---|---|---|---|
| TA1G | 240 | 140 | 25 | 30 | |
| TA2G | 400 | 275 | 20 | 30 | |
| TA3G | 500 | 380 | 18 | 25 | |
| TA4G | 580 | 485 | 15 | 25 | |
| TA5 | 685 | 585 | 13 | 25 | |
| TA6 | 685 | 585 | 13 | 25 | |
| TA7 | 785 | 680 | 10 | 20 | |
| TA9 | 370 | 250 | 20 | 30 | |
| TA10 | 485 | 345 | 18 | 25 | |
| TA13 | 540 | 400 | 15 | 25 | |
| TA15 | 885 | 825 | 10 | 15 | |
| TA18 | 620 | 518 | 12 | 25 | |
| TA19 | 895 | 825 | 10 | 15 | |
| TB2 | <980 | 825 | 10 | 20 | |
| TB6 | 1,370 | 1,100 | 10 | 15 | |
| TC1 | 1,105 | 1,035 | 15 | 30 | Solution treatment |
| TC2 | 585 | 460 | 25 | 30 | Solution aging treatment |
| TC3 | 685 | 560 | 10 | 25 | |
| TC4 | 800 | 680 | 10 | 25 | |
| TC4ELI | 895 | 825 | 10 | 15 | |
| TC6 | 980 | 840 | 10 | 25 | Regular annealing for TC6 bars |
| TC9 | 1,060 | 910 | 10 | 25 | |
| TC10 | 1,030 | 900 | 10 | 25 | |
| TC11 | 1,030 | 910 | 10 | 25 | |
| TC12 | 1,150 | 1,000 | 10 | 25 | |
| TC17 | 1,120 | 1,030 | 10 | 25 | |
| TC18 | 1,080 – 1,280 | 1,010 | 10 | 25 | |
| TC21 | 1,100 | 1,000 | 10 | 25 | |
| TC25 | 980 | 925 | 10 | 25 |
Note: The properties of TC6 bars are measured in the standard annealed state. If requested by the purchaser and stated in the order, the properties can be measured in the isothermal annealed state.
Table 3. high-temperature mechanical properties
| Cijfer | Test Temperature (°C) | Tensile Strength (R<sub>m</sub>) (MPa) | Test Stress (σ) (MPa) | Test Duration (h) |
|---|---|---|---|---|
| TA6 | 350 | 420 | 390 | 100 |
| TA7 | 350 | 490 | 440 | 100 |
| TA15 | 500 | 570 | 470 | 50 |
| TA18 | 350 | 340 | 320 | 100 |
| TA19 | 400 | 310 | 280 | 100 |
| TC1 | 480 | 620 | 480 | 35 |
| TC2 | 350 | 345 | 325 | 100 |
| TC4 | 350 | 420 | 390 | 100 |
| TC6 | 400 | 685 | 560 | 100 |
| TC9 | 400 | 785 | 685 | 50 |
| TC10 | 500 | 835 | 590 | 100 |
| TC11 | 400 | 685 | 785 | 35 |
| TC12 | 500 | 885 | 640 | 100 |
| TC17 | 500 | 735 | 590 | 100 |
| TC25 | 400 | 685 | 685 | 50 |
Note: If the long-term performance of TC11 titanium alloy bars does not meet the requirements, it is permissible to conduct a test at 500°C with a test stress of 590 MPa for ≥100 hours. If this test passes, the batch of bars is considered to meet the long-term performance requirements.
5.4 Transition Temperature Upon request and specification in the purchase order, the bars should provide the transition temperature B according to the smelting furnace number.
5.5 Ultrasonic Testing Upon request and specification in the purchase order, the bars should undergo ultrasonic testing. The acceptance level shall be determined through negotiation between the supplier and the purchaser.
5.6 Low Magnification Microstructure The low magnification microstructure of the bars should be free from cracks, shrinkage, porosity, metal or non-metallic inclusions, segregation affecting use, and other visible metallurgical defects.
5.7 Microstructure Upon request and specification in the purchase order, the material should undergo evaluation of microstructure. The evaluation requirements shall be determined through negotiation between the supplier and the purchaser.
5.8 Appearance Quality 5.8.1 Bars should be supplied with a polished surface. The surface roughness (Ra) of the bars should not exceed 3.2μm. 5.8.2 Minor scratches, indentations, pits, wrinkles, and other defects on the surface of the bars are allowed, provided they do not exceed half of the allowable deviation in diameter or thickness. 5.8.3 Local defects on the surface of the material should be removed. The depth of cleaning should not exceed the allowable deviation of the corresponding dimension of the product. The ratio of depth to width of the cleaned area should not exceed 1:6.
6. Test Methods
6.1 Chemical Composition The chemical composition analysis of the product should be conducted in accordance with the provisions of GB/T4698 (all parts) or YS/T1262, and arbitration analysis should be carried out according to the provisions of GB/T4698 (all parts).
6.2 Dimensions and Permissible Variations The measurement of the product’s dimensions and permissible variations should be carried out according to the provisions of GB/T38982.
6.3 Room Temperature Tensile Properties The test of the product’s room temperature tensile properties should be conducted according to the provisions of GB/T228.1-2021. The R7 specimen should be used for testing.
6.4 High-Temperature Tensile Properties The test of the product’s high-temperature tensile properties should be conducted according to the provisions of GB/T228.2.
6.5 Persistent Performance The test of the product’s persistent performance should be conducted according to the provisions of GB/T2039.
6.6 B Transition Temperature The test of the product’s B transition temperature should be conducted according to the provisions of GB/T23605.
6.7 Ultrasonic Testing The ultrasonic testing of the product should be conducted according to the provisions of GB/T5193.
6.8 Low Magnification and Microstructure The inspection of the product’s low magnification and microstructure should be conducted according to the provisions of GB/T5168.
6.9 Appearance Quality The appearance quality of the product should be inspected visually. The surface roughness of the bars should be inspected using the standard sample block comparison method.
7.1 Inspection and Acceptance
7.1.1 The products shall be inspected by the supplier or a third party to ensure that the product quality meets the requirements of this document and the order.
7.1.2 The buyer may inspect the received products according to the provisions of this document. If the inspection results do not conform to the provisions of this document or the order, they shall be notified to the supplier in writing and resolved through negotiation between the two parties. Objections to the shape and size and their allowable tolerances, and the appearance quality shall be raised within one month from the date of receipt of the products; objections to the chemical composition, mechanical properties, low-power organization, microstructure, and ultrasonic testing shall be raised within three months from the date of receipt of the products. In case of arbitration, the buyer and the supplier shall jointly sample or reach an agreement on sampling.
7.2 Batching
Products shall be submitted for acceptance in batches, each batch consisting of products of the same brand, heat number, specification, manufacturing method, state, and heat treatment batch.
7.3 Inspection Items
Each batch of products shall be inspected for chemical composition, shape and size and their allowable tolerances, tensile properties at elevated temperature, low-power organization and appearance quality. High-temperature mechanical properties, transition temperature, ultrasonic testing and microstructure shall also be inspected when specified in the order.
7.4 Sampling
Product sampling shall comply with the provisions of Table 4.
| Product type | Sampling method |
|---|---|
| Bars, rods, tubes, profiles, strips, and plates | Take samples from each batch, and the sampling location shall be evenly distributed along the length of the product. The number of samples shall be determined according to the following table: |
| Batch size (t) | |
| ≤50 | |
| 51-100 | |
| 101-200 | |
| >200 | |
| Forgings and castings | Take samples from each batch, and the sampling location shall be representative of the product quality. The number of samples shall be determined according to the following table: |
| Batch size (pieces) | |
| ≤50 | |
| 51-100 | |
| 101-200 | |
| >200 | |
| Welded products | Take samples from each batch of welds, and the sampling location shall be representative of the weld quality. The number of samples shall be determined according to the following table: |
| Batch size (m) | |
| ≤50 | |
| 51-100 | |
| 101-200 | |
| >200 |
7.5 Judgment of Inspection Results
7.5.1 If the chemical composition test results do not meet the requirements, the batch of products shall be judged unqualified.
7.5.2 If the test results for shape and size and their allowable tolerances, ultrasonic testing, and appearance quality are not qualified, the corresponding product shall be judged unqualified. Echter, the supplier may remove the unqualified parts and re-inspect them. If they are qualified, they shall be re-batched and delivered.
7.5.3 If the mechanical performance test results are not qualified, double the number of test pieces shall be taken from the batch of products for retesting. If one test piece is still unqualified after retesting, the batch of products shall be judged unqualified. Echter, the supplier may inspect each product individually, and those that are qualified shall be re-batched and delivered. Alternatively, the products may be re-heat treated and re-sampled for inspection.
7.5.4 If the low-power organization and microstructure test results are not qualified, the batch of products shall be judged unqualified.
8 Marking, Packaging, Transportation, Storage, and Accompanying Documents
8.1 Marking
8.1.1 Product Marking
Qualified products shall be marked (or labeled) with the following information:
A) Supplier name; b) Brand; c) Specificatie; d) State; e) Batch number; f) Document number.
8.1.2 Packaging Marking
The packaging marking of the products shall comply with the provisions of GB/T8180.
8.2 Packaging, Transportation, and Storage
The packaging, transportation, and storage of the products shall comply with the provisions of GB/T8180.
8.3 Accompanying Documents
Each batch of products shall be accompanied by accompanying documents, which, in addition to the supplier information, product information, document number, and date of manufacture or packaging, should also include the following:
A) Quality certificate, which shall include the following contents: Product name, brand, specification and state; Product ingot number, batch number, batch weight and quantity; Main performance and technical parameters of the product; Analytical inspection results and quality inspection department seal; Others.
b) Certificate of conformity, which shall include the following contents: Ingot or batch number; Inspection date; Inspector’s signature or seal; Others.
c) Others.
9 Contents of Order Form
The buyer may, according to its own needs, list the following contents in the order form for the products listed in this document:
A) Product name; b) Brand; c) Specificatie; d) State; e) Weight; f) Quantity; g) Document number; h) Others.