Which is better, pure titanium or titanium alloy?

Titanium is a chemical element with the chemical symbol Ti and the atomic number 22. It is located in the 4th period and the IVB group in the periodic table of chemical elements. It is a silvery white transition metal characterized by light weight, high strength, metallic luster, and resistance to wet chlorine corrosion. Titanium is resistant to aqua regia corrosion, but not to sulfuric acid, hydrochloric acid, and high concentrations of nitric acid; boiling salt water and boiling sodium hydroxide solutions can also corrode titanium. However, titanium is easily corroded by some reagents at high temperatures. Titanium is considered a rare metal because it is dispersed in nature and difficult to extract.

 

Titanium alloy is an alloy composed of titanium and other elements. Titanium has two isomorphous crystals: titanium is an allotrope with a melting point of 1720℃. When it is below 882℃, it presents a close-packed hexagonal lattice structure, called α titanium; when it is above 882℃, it presents a body-centered cubic lattice structure, called β titanium. Taking advantage of the different characteristics of the above two structures of titanium, appropriate alloying elements are added to gradually change its phase transition temperature and phase content to obtain titanium alloys with different structures.

 

In simple terms, pure titanium: pure titanium is titanium with a titanium content of more than 99.%, without any metal, and has the advantages of high and low temperature resistance, corrosion resistance, low density, and high strength. Generally speaking, titanium content higher than 95% is called industrial pure titanium. Pure titanium is divided into TA1-TA4 according to the titanium content and impurity content. We usually see TA1 and TA2. After removing impurities such as oxygen, nitrogen, hydrogen, carbon, iron, etc., the remaining content is basically titanium. The higher the titanium content, the softer it is, and the lower the strength, but the better its toughness. Although industrial pure titanium is a close-packed hexagonal lattice at room temperature, its axis is relatively small (c/a=1.587), and it has good processability. Pure titanium has good forming and welding properties and is not sensitive to heat treatment. Therefore, when we make titanium belt buckles and titanium jewelry titanium equipment, we will use TA1 materials in places where the force is not very strong, and TA2 materials will be used for shafts, small screws, molds, parts, fixtures, turning, etc.

 

Titanium alloy: Alloy is titanium doped with a part of other metals, called alloy. It is an alloy material composed of titanium and other strengthening elements, such as aluminum, nickel, chromium, copper, etc., in order to obtain higher strength, corrosion resistance, and high temperature resistance. Titanium alloy is a single-phase alloy composed of a phase solid solution, with low density. Whether at normal temperature or at a higher actual application temperature, it is a phase, with stable structure, higher wear resistance than pure titanium, and strong oxidation resistance. At a temperature of 500-600 degrees, it still maintains its strength and creep resistance, can be strengthened by heat treatment, has good thermal strength and thermal stability, good welding performance, and good room temperature, ultra-low temperature and high temperature performance. At present, titanium alloy is the most widely used titanium metal material, and is widely used in aviation materials, oil extraction, food, sports, medical fields, etc. The concepts of titanium alloy and pure titanium are different, the material composition is also different, and their respective scopes of application are also different.

 

Compared with titanium alloy and pure titanium, the market price of pure titanium is lower than that of titanium alloy. At present, the market price of pure titanium is about 80-150 yuan per kilogram lower than that of titanium alloy with the same specifications. For reference only!