Comparison Of The Properties Of Titanium And Tantalum Metals

Titanium metal:
Titanium strength, pure titanium tensile strength of up to 180kg/mm2. some steel strength is higher than titanium alloy, but the specific strength of titanium alloy (tensile strength and density ratio) is more than high quality steel. Titanium alloy has good heat-resistant strength, low-temperature toughness and fracture toughness, so more used as aircraft engine parts and rockets, missile structure. Titanium alloy can also be used as fuel and oxidizer storage tanks and high-pressure containers. Now there are titanium alloys used in the manufacture of automatic rifles, mortar plates and recoilless cannon launch tubes. In the petroleum industry, mainly for a variety of containers, reactors, heat exchangers, distillation towers, pipelines, pumps and valves. Titanium can be used as electrodes and power station condensers and environmental pollution control devices. Titanium-nickel shape memory alloy has been widely used in instrumentation. In the medical treatment, titanium can be used as artificial bones and various appliances. Titanium is also a deoxidizer for steelmaking and a component of stainless steel and alloy steel. Titanium dioxide is a good raw material for pigments and paints. Titanium carbide, titanium carbide (hydrogen) is a new type of hard alloy material. Titanium nitride color close to gold, widely used in decoration.
Titanium and titanium alloys are widely used in the aviation industry, known as "space metal"; in addition, there is an increasingly wide range of applications in the shipbuilding industry, the chemical industry, the manufacture of mechanical components, telecommunications equipment, cemented carbide, etc. In addition, titanium alloys have been widely used in the aviation industry.
In addition, because titanium alloy also has good compatibility with the human body, so titanium alloy can also be used as artificial bone.

Tantalum metal:
Used in metal alloys. Tantalum pentoxide is used in capacitors. Tantalum is also used in cutting tools, vacuum filaments, and camera lenses.
Tantalum's texture is very hard, the hardness can reach 6-6.5. Its melting point is up to 2996 ℃, after tungsten and rhenium, ranked third. Tantalum is malleable and can be drawn into a thin, filamentary foil. Its coefficient of thermal expansion is very small, every one degree Celsius only six point six percent expansion. In addition to this, it is very tough, more so than copper.
Tantalum also has excellent chemical properties and is highly resistant to corrosion. It does not react to hydrochloric acid, concentrated nitric acid or "aqua regia", neither in cold nor in hot conditions. But tantalum can be corroded in hot concentrated sulfuric acid, below 150, tantalum will not be corroded by concentrated sulfuric acid, only at temperatures higher than this will have a reaction, in 175 degrees of concentrated sulfuric acid for 1 year, was corroded by the thickness of 0.0004 millimeters, tantalum into 200 ℃ sulfuric acid immersion for a year, the surface layer is only damaged 0.006 millimeters. At 250 degrees, the corrosion rate increased, for each year was corroded thickness of 0.116 mm, at 300 degrees, was corroded more quickly, immersed in 1 year, the surface was corroded 1.368 mm. In fuming sulfuric acid (containing 15% SO3) corrosion rate than in concentrated sulfuric acid is more serious, in 130 degrees of the solution immersed in 1 year, the surface was corroded thickness of 15.6 mm. Tantalum will also be corroded by phosphoric acid at high temperature, but the reaction generally occurs above 150 degrees, in 250 degrees of 85% phosphoric acid, immersed in 1 year, the surface was corroded 20 mm, in addition, tantalum in the mixed acid of hydrofluoric acid and nitric acid can be dissolved quickly. But tantalum is more afraid of strong alkali, in 110 degrees 40% concentration of caustic soda solution, tantalum will be quickly dissolved, in the same concentration of potassium hydroxide solution, as long as 100 degrees will be quickly dissolved. In addition to the above, general inorganic salts can not corrode tantalum below 150 degrees. Experiments have proved that tantalum at room temperature, alkali solution, chlorine, bromine, dilute sulfuric acid and many other agents are not effective, only in the role of hydrofluoric and hot concentrated sulfuric acid reaction. Such a situation is relatively rare in metals.
However, at high temperatures, the oxide film on the surface of tantalum is destroyed, so it can react with a variety of substances, and at room temperature tantalum can react with fluorine. At 150 degrees, tantalum is inert to chlorine, bromine and iodine, at 250 degrees, tantalum is still corrosion resistant to dry chlorine, in the chlorine containing water vapor heated to 400 degrees, can still keep bright, at 500 degrees is beginning to be corroded, tantalum and bromine at 300 degrees or more, to iodine vapor when the temperature reaches the red heat before are inert. Hydrogen chloride reacts with tantalum at 410 degrees to produce pentachloride, while hydrogen bromide reacts with tantalum at 375 degrees. S reacts with Ta when heated to 200 degrees or less, and carbon and hydrocarbons react with tantalum at 800-1100 degrees.
Tantalum has a wide range of applications due to its properties. In the preparation of a variety of inorganic acid equipment, tantalum can be used to replace stainless steel, life than stainless steel dozens of times. In addition, in the chemical, electronics, electrical and other industries, tantalum can replace the past need to be borne by the precious metal platinum task, so that the required cost is greatly reduced. Tantalum is manufactured into capacitors equipped with military equipment.