What Is The Difference Between Titanium Steel, Pure Titanium, And Titanium Alloy?

The name titanium steel is not a standard academic name, but a commercial name. Because the corrosion resistance and acid and alkali resistance of 316L stainless steel are better than ordinary stainless steel, the standard grade is 022Cr17Ni12Mo2, which mainly contains Cr, Ni, Mo, and the number indicates the approximate percentage contained.

 

It can be seen that titanium steel does not contain titanium, and its main component is still iron. This commercial name is to distinguish it from other stainless steels and obtain higher value when used as jewelry. In fact, the cost and sweat corrosion resistance of 316L stainless steel are indeed better than common stainless steel.

 

And what can really be called titanium materials generally fall into two categories, one is pure titanium, and the other is titanium alloy.

 

The one with the highest titanium content is the just-made sponge titanium, which is formed by reducing titanium tetrachloride with magnesium. It looks like this:

 

It is loose and porous, and its strength is very low. It cannot be directly used as titanium material. It is the most upstream material of titanium material. After smelting, forging, rolling, it is processed into various shapes of plates, wires, tubes, etc.

 

The titanium content of titanium sponge is close to 100%. However, titanium is too active, and it is easy to react with oxygen, nitrogen, hydrogen, etc. in the air when exposed to air, so it is almost impossible to have a complete 100% purity.

 

Generally speaking, if the titanium content is higher than 95%, it becomes industrially pure titanium. Pure titanium is divided into TA1-TA4 according to the titanium content and impurity content. We usually see TA1 and TA2 more commonly. Impurities are mainly oxygen, nitrogen, hydrogen, carbon, iron and so on. The higher the titanium content, the softer it is, the lower the strength we say, but the better its toughness.

 

Therefore, when we make titanium belt buckles and titanium accessories, we will use TA1 material in places where the force is not very strong, and we will use TA2 material for shafts and small screws.

 

When we make pure titanium cups, we cannot use TA2. The higher the purity, the better, especially the low hydrogen content. Otherwise, because of insufficient toughness, it is easy to crack, or there will be more obvious stretch lines one by one. Or pitting, the reject rate will be quite high.

 

Next, titanium alloys, as the name suggests, are alloys formed of titanium and other metals and non-metals. These metals and nonmetals such as aluminum, molybdenum, vanadium, chromium, iron, zirconium, tin, oxygen, carbon, etc. Titanium alloys are divided into TA, TB, and TC series according to the different metallographic structures. I won't go into details here.

 

Take the most commonly used TC4 titanium alloy as an example, its titanium content is 90%, aluminum 6%, vanadium 4%, so it is also called titanium 6 aluminum 4 vanadium. TC4 titanium alloy is the earliest developed and most widely used titanium alloy in the world, and it is also the earliest titanium alloy used in medical treatment. Its output accounts for more than half of the total output of various titanium alloy products in the world, especially in the aerospace industry. More than 80%. It has high-strength anti-corrosion performance, higher strength than pure titanium, good toughness, relatively easy processing and welding, so its comprehensive performance is excellent, and it will not cause allergies like pure titanium.

 

Then is pure titanium or titanium alloy better?

 

This is inconclusive. Different materials are suitable for different products. Generally speaking, the material cost of titanium alloy is higher than that of pure titanium, excluding factors such as shape. Of course, the titanium alloy here needs to be of a regular grade, which is based on titanium and other metals and non-metals are added, rather than adding a little titanium to other metals, which contains a little titanium and pretends to be a titanium alloy.