Titanium Alloy Plates And Welding Specifications

1、The scope of application

(1) This section applies to titanium alloy plates with thickness of 3mm and above for ships or ocean engineering.

(2) If titanium alloy plates other than those specified in this section are used, the chemical composition, mechanical properties and application situation shall be submitted to CCS for review and acceptance according to the relevant accepted standards.

2、The manufacturing

（1) Titanium alloy plate shall be manufactured by a factory approved by CCS.

（2) In addition to the provisions of this section, titanium alloys shall be manufactured and tested in accordance with the relevant provisions of Chapters 1 and 2 of this section.

（3) Titanium alloy smelting should be carried out under vacuum conditions. If the vacuum self-consumption furnace is used for remelting, the consumable electrode shall be prohibited to use tungsten-electrode argon arc melting for no less than two times to ensure the chemical uniformity of the material.

（4) Titanium alloy plate should usually be made by rolling method.

（5) Unless specified in the contract, titanium alloy plates are usually delivered in the annealed state.

3、Surface quality

(1）There should be no defects affecting the use of the plate surface, such as cracks, skinning, oxide skinning, wrinkles, metal or non-metal inclusions, alkali wash marks

(2）Titanium alloy plate product edge should be flat, no burr, size and tolerance range should meet the relevant technical conditions accepted by CCS.

 (3)  Slight surface defects are allowed to be removed by grinding. Grinding should generally be carried out in the rolling direction, and the surface after grinding should form a smooth transition, and the minimum thickness specified by the operating conditions. Repair of surface defects by welding is not allowed.

4、Chemical composition

The titanium alloy ingot plant shall conduct chemical composition analysis for each furnace product. The chemical composition shall meet the requirements of Table 1.

Table 1 Chemical Composition of titanium Alloy (%)

Note: ALL VALUES IN THE TABLE ARE THE maximum values EXCEPT THOSE with intervals.

5、Mechanical properties

(1) At least 1 sheet should be selected from the plates of each batch (same furnace number, same manufacturing method, same thickness, same heat treatment furnace) (when one batch, 2 sheets should be selected), and a test material should be cut from the end of the plate to the edge of the plate about 1/4 plate width.

(2) One tensile specimen and one group of 3 Charpy impact specimens (with plate thickness greater than 10mm) and two specimens shall be prepared for each sample according to the following requirements:

①The tensile sample should be used in Table 2.2.2.1 in chapter 2 of this section, the plate proportion sample of serial number 1 (but the sample width can be 12.5mm P7 degree is greater than 40mm can also be used the round bar proportion sample of serial number 2 (but the sample diameter can be 5mm), at this time the axis of the sample should be located at the plate;

②when the thickness of the plate is not more than 40mm, the impact sample should be the sample edge from the plate rolling surface is not more than 2mm; If the product is 40mm thick, the axis of the sample should be located at 1/4 thickness of the plate. The axis of the sample should be perpendicular to the rolling direction, and the notch of the sample should be perpendicular to the rolling

③The drawing surface of the two bending samples should maintain at least one original rolling surface, and its axis should be perpendicular to the rolling direction. The width of the sample is 15 and the thickness of the plate is more than 5mm, which can be thinned to 5mm on one side.

(3) Specimen preparation and testing of mechanical properties shall be carried out in accordance with the relevant provisions of Chapter 2 of this article. Both rolled surfaces of the plate shall be tested in the bending test.

(4) Mechanical properties of titanium alloy shall meet the requirements of Table II.

Table 2 Mechanical properties of titanium alloys

6、Non-destructive testing

If the contract stipulates that the board shall be nondestructive tested, the nondestructive test shall be carried out as required by the contract.

7、Identification and Certificate

(1) The plate manufacturer clearly marks the CCS inspection mark and the following mark on each piece of titanium plate (sheet can be stacked and packed) that passes the inspection:

①Name of the manufacturer;

②Brand number and delivery status of materials;

③Numbers or abbreviations that can trace the entire production process of titanium materials;

④If the ordering party so requires, the ordering contract number or other identification mark can be marked.

(2) Each batch of plates shall be accompanied by a certificate of conformity of the materials. The certificate of conformity shall include at least the following:

①Orderer's name and Contract number;

②Material brand number, furnace batch number and delivery status;

③Specifications and quantity of materials;

④Chemical composition and mechanical properties of materials.