Alpha alloy contains a certain amount of stable alpha, which is mainly composed of alpha. It has a small weight, good thermal strength, good weldability and excellent corrosion resistance. The disadvantage is that the room temperature is low, usually used as heat resistant material and corrosion resistant material. Alpha alloys are usually divided into all-alpha alloys (TA7), near-alpha alloys (ti-8al-1m-to-1v) and alpha alloys with a small number of compounds (ti-2.5 Cu).

 

The composition of titanium alloys can be divided into three types: alpha alloy (alpha + beta) and beta alloy, respectively, in terms of TA, TC and TB.

 

The alpha alloy contains a certain amount of stable alpha, which is mainly composed of alpha. It has a small weight, good thermal strength, good weldability and excellent corrosion resistance. The disadvantage is that the room temperature is low, usually used as heat resistant material and corrosion resistant material. Alpha alloys are usually divided into all-alpha alloys (TA7), near-alpha alloys (ti-8al-1m-to-1v) and alpha alloys with a small number of compounds (ti-2.5 Cu). (alpha + beta) alloy contains a certain amount of stable alpha phase and beta phase, and the equilibrium state of the alloy is alpha and beta phase. (alpha + beta) alloy has moderate strength and can be treated with heat treatment, but the welding performance is poor. (alpha + beta) alloys are widely used, and the yield of ti-6al-4v alloy is more than half of the total titanium.

 

The beta alloy contains a large number of elements that stabilize beta phase, which can retain the high temperature beta phase to room temperature. Beta alloys can also be divided into treatable beta alloys (substable beta alloys and near-metastable beta alloys) and thermal stable beta alloys. The heat-treatable beta alloy has excellent plasticity in quenching state, and the tensile strength can be reached between 130 and 140kgf/mm2 by aging treatment. Beta alloys are used for high strength and high toughness materials. Disadvantages are higher than major, high cost, poor welding performance, cutting processing difficulties.

 

Technical requirements

 

1. The chemical composition of titanium and titanium alloy bars shall conform to GB/T 3620.1, and the allowable deviation of chemical composition shall conform to the provisions of GB/T 3620.2 for repeated inspection.

 

2: the diameter or length of the hot working rod and its allowable deviation shall be in accordance with the provisions of table 1.

 

3: the diameter of the cold-drawn rod should be in accordance with the provisions of table ii.

 

4: the non-roundness of the light rod after the hot processing shall not be greater than half of its dimensions.

 

5. The length of the indefinite length of the processed rod is 300-6000mm, the length of the annealed state rod is 3000-2000mm, and the length of the ruler or the length of the rod should be within the range of the indeterminate scale. The length of the fixed length is allowed to be 0.20mm. The length of the length shall also be included in the cut of the rod, and the amount of each bite shall be 5mm. The length of the ruler or the length shall be indicated in the contract.

 

Titanium is an important structural metal developed in the 1950s. Titanium alloy has been widely used in various fields due to its advantages of high strength, corrosion resistance and high heat resistance. Many countries in the world have realized the importance of titanium alloy materials and have been developing and developing them. Titanium is the first Ⅳ class B elements in the periodic table, appearance is like steel, melting point 672 ℃, 1 genus refractory metal. Titanium is abundant in the crust, which is much higher than Cu, Zn, Sn, Pb and other common metals. China's titanium resources are extremely rich, and in sichuan panzhihua region, there are about 420 million tons of titanium in the special large-scale vanadium titanium magnetite, which is close to the total of proved titanium reserves in foreign countries. Titanium alloy can be divided according to the use, high strength alloy, heat-resistant alloy corrosion resistant alloy, titanium, molybdenum, titanium and palladium alloy etc.), low-temperature alloy and special function (titanium - hydrogen storage materials of iron and nickel titanium memory alloy), etc.