Tantalum Titanium Alloy
Overview of Tantalum-titanium alloy
Tantalum-titanium alloy is a binary or multi-component alloy formed by using titanium as the matrix (with the titanium content typically ranging from 50% to 90%), and adding tantalum as the main alloying element. Some grades may also include a small amount of other elements (such as zirconium, niobium) as per the requirements to further optimize the performance.
Tantalum (Ta) and titanium (Ti) are both refractory metals with excellent properties. The tantalum-titanium alloy formed by them combines the core advantages of both metals and compensates for the shortcomings of a single metal through composition control, thus holding an irreplaceable position in high-end industrial fields.
The preparation process of tantalum-titanium alloy
Since tantalum and titanium are both highly reactive metals (they readily react with oxygen and nitrogen), and their melting points differ significantly, the alloy preparation must be carried out in an inert atmosphere (argon) or in a vacuum environment. The core process includes:
Melting process: Vacuum Arc Melting (VAR) and Electron Beam Melting (EB), used for preparing uniform alloy ingots;
Powder preparation: Plasma atomization (PA), Hydrogenation and dehydrogenation (HDH), converting the alloy ingot into ultrafine powder, suitable for 3D printing;
Powder preparation: Plasma atomization (PA), Hydrogenation and dehydrogenation (HDH), converting the alloy ingot into ultrafine powder, suitable for 3D printing;
Forming and processing: Through hot forging, cold rolling (taking advantage of the excellent plasticity of alloys), or additive manufacturing technologies such as laser powder bed fusion (LPBF) and electron beam melting (EBM), complex components can be formed.
The properties of tantalum-titanium alloy
Mechanical Properties
High strength: The room temperature tensile strength of Ta-10Ti is approximately 800-900 MPa (pure tantalum is about 260 MPa, pure titanium is about 550 MPa);
Excellent plasticity: The elongation rate can reach 15% - 25%, far exceeding that of refractory metals such as tungsten and molybdenum (< 5%).
High temperature strength stability: The tensile strength at 600℃ remains above 70% of the value at room temperature.
High strength: The room temperature tensile strength of Ta-10Ti is approximately 800-900 MPa (pure tantalum is about 260 MPa, pure titanium is about 550 MPa);
Excellent plasticity: The elongation rate can reach 15% - 25%, far exceeding that of refractory metals such as tungsten and molybdenum (< 5%).
High temperature strength stability: The tensile strength at 600℃ remains above 70% of the value at room temperature.
Corrosion Resistance
Resistance to chemical corrosion: It has a corrosion resistance similar to pure tantalum (pure tantalum is known as the "King of Corrosion Resistant Metals") in hydrochloric acid, sulfuric acid (concentration < 50%), and organic acids.
Resistance to high-temperature oxidation: Below 500℃, the oxidation rate is extremely low. A dense Ta2O5-TiO2 composite oxide film forms on the surface, preventing further corrosion.
Resistance to chemical corrosion: It has a corrosion resistance similar to pure tantalum (pure tantalum is known as the "King of Corrosion Resistant Metals") in hydrochloric acid, sulfuric acid (concentration < 50%), and organic acids.
Resistance to high-temperature oxidation: Below 500℃, the oxidation rate is extremely low. A dense Ta2O5-TiO2 composite oxide film forms on the surface, preventing further corrosion.
Physical Properties
Low density: Ta-10Ti density is about 15.5 g/cm3 (pure tantalum is 16.65 g/cm3), while that of Ta-40Ti is about 12.8 g/cm3, which is significantly lower than that of pure tantalum.
High thermal and electrical conductivity: The thermal conductivity is approximately 50-60 W/(m·K), similar to pure tantalum and much higher than that of titanium alloys (such as TC4, which is about 11 W/(m·K));
Low vapor pressure: At high temperatures, the vapor pressure is low, making it difficult to volatilize. This property makes it suitable for applications in vacuum environments.
Low density: Ta-10Ti density is about 15.5 g/cm3 (pure tantalum is 16.65 g/cm3), while that of Ta-40Ti is about 12.8 g/cm3, which is significantly lower than that of pure tantalum.
High thermal and electrical conductivity: The thermal conductivity is approximately 50-60 W/(m·K), similar to pure tantalum and much higher than that of titanium alloys (such as TC4, which is about 11 W/(m·K));
Low vapor pressure: At high temperatures, the vapor pressure is low, making it difficult to volatilize. This property makes it suitable for applications in vacuum environments.
Biocompatibility
It has no cytotoxicity, and its surface can easily form hydroxyapatite coating (similar to the components of human bones), and the release of metal ions is extremely low (much lower than that of titanium alloys).
It has no cytotoxicity, and its surface can easily form hydroxyapatite coating (similar to the components of human bones), and the release of metal ions is extremely low (much lower than that of titanium alloys).
Application of tantalum-titanium alloys
Aerospace and Defense
Aerospace engineering is the core application field of tantalum-titanium alloys, and it is particularly suitable for high-temperature, high-pressure and lightweight requirements.
Engine components: For turbine blades and combustion chamber liners (Ta-10Ti/Ta-20Ti), by leveraging their high-temperature strength and resistance to gas corrosion, they can withstand gas temperatures of 800-1000℃.
Spacecraft structural components: Valve cores of the satellite attitude control system, nozzle components of the rocket propulsion system (Ta-40Ti), utilize the advantage of low density to reduce the spacecraft's weight, while resisting high-temperature radiation and atomic oxygen erosion in the space vacuum environment.
Nuclear industry components: Control rod cladding tubes for nuclear reactors (Ta-15Ti), resistant to strong radiation and high-temperature molten salt corrosion, with a low neutron absorption cross-section, which does not affect the efficiency of nuclear reactions.
Aerospace engineering is the core application field of tantalum-titanium alloys, and it is particularly suitable for high-temperature, high-pressure and lightweight requirements.
Engine components: For turbine blades and combustion chamber liners (Ta-10Ti/Ta-20Ti), by leveraging their high-temperature strength and resistance to gas corrosion, they can withstand gas temperatures of 800-1000℃.
Spacecraft structural components: Valve cores of the satellite attitude control system, nozzle components of the rocket propulsion system (Ta-40Ti), utilize the advantage of low density to reduce the spacecraft's weight, while resisting high-temperature radiation and atomic oxygen erosion in the space vacuum environment.
Nuclear industry components: Control rod cladding tubes for nuclear reactors (Ta-15Ti), resistant to strong radiation and high-temperature molten salt corrosion, with a low neutron absorption cross-section, which does not affect the efficiency of nuclear reactions.
Medical implantation field
Tantalum-titanium alloys have gained popularity as an ideal material for high-end medical implants due to their excellent biocompatibility and mechanical compatibility.
Orthopedic implants: artificial hip joint prostheses, spinal fusion cages (Ta-10Ti), with an elastic modulus of approximately 110-130 GPa, are close to that of human cortical bone (about 10-30 GPa).
Although still higher than that of bone, it is much lower than the 186 GPa of pure tantalum, which can reduce the "stress shielding effect" (preventing bone atrophy due to insufficient force).
Dental prostheses: Implant abutments (Ta-5Ti), with a surface that readily forms a bioactive coating, bond closely with gingival tissue and are resistant to corrosion from saliva and oral bacteria, with a service life of over 15 years.
Cardiovascular devices: The outer shell of the cardiac pacemaker (Ta-20Ti) has both antibody liquid corrosion resistance and electromagnetic shielding properties, protecting the internal circuitry from interference by the human environment.
Tantalum-titanium alloys have gained popularity as an ideal material for high-end medical implants due to their excellent biocompatibility and mechanical compatibility.
Orthopedic implants: artificial hip joint prostheses, spinal fusion cages (Ta-10Ti), with an elastic modulus of approximately 110-130 GPa, are close to that of human cortical bone (about 10-30 GPa).
Although still higher than that of bone, it is much lower than the 186 GPa of pure tantalum, which can reduce the "stress shielding effect" (preventing bone atrophy due to insufficient force).
Dental prostheses: Implant abutments (Ta-5Ti), with a surface that readily forms a bioactive coating, bond closely with gingival tissue and are resistant to corrosion from saliva and oral bacteria, with a service life of over 15 years.
Cardiovascular devices: The outer shell of the cardiac pacemaker (Ta-20Ti) has both antibody liquid corrosion resistance and electromagnetic shielding properties, protecting the internal circuitry from interference by the human environment.
Chemical Engineering and Energy
In harsh corrosive and high-temperature environments such as those found in chemical and energy industries, tantalum-titanium alloys can replace expensive platinum alloys or Hastelloy alloys.
Chemical equipment: Inner lining of reaction vessels for strong acid solutions (such as hydrochloric acid, acetic acid), heat exchanger tubes (Ta-10Ti), has corrosion resistance close to pure tantalum, but the cost is 20%-30% lower than that of pure tantalum;
New energy field: The connector (Ta-30Ti) for solid oxide fuel cells (SOFC) maintains its conductivity and structural stability in an oxidizing atmosphere at temperatures ranging from 700 to 800 degrees Celsius, and is more resistant to high-temperature oxidation compared to traditional stainless steel.
Electrolytic industry: Inert electrodes (Ta-15Ti) for electrolytic aluminum and copper production, which prevent electrode dissolution and contamination of the electrolyte, thereby enhancing product purity.
Chemical equipment: Inner lining of reaction vessels for strong acid solutions (such as hydrochloric acid, acetic acid), heat exchanger tubes (Ta-10Ti), has corrosion resistance close to pure tantalum, but the cost is 20%-30% lower than that of pure tantalum;
New energy field: The connector (Ta-30Ti) for solid oxide fuel cells (SOFC) maintains its conductivity and structural stability in an oxidizing atmosphere at temperatures ranging from 700 to 800 degrees Celsius, and is more resistant to high-temperature oxidation compared to traditional stainless steel.
Electrolytic industry: Inert electrodes (Ta-15Ti) for electrolytic aluminum and copper production, which prevent electrode dissolution and contamination of the electrolyte, thereby enhancing product purity.
Electronics and Precision Manufacturing
By taking advantage of its high thermal conductivity and low vapor pressure properties, tantalum-titanium alloys are used in the electronic field for key components:
Semiconductor manufacturing: The vacuum chamber components (Ta-20Ti) of the chip deposition process resist corrosion by plasmas (such as fluorine plasma), and have a low vapor pressure to avoid contaminating the chip surface.
High-end instruments: Ion source electrodes (Ta-10Ti) for mass spectrometers and spectrometers. The high conductivity and high thermal resistance ensure the stable operation of the instruments in high vacuum and high temperature environments.
Semiconductor manufacturing: The vacuum chamber components (Ta-20Ti) of the chip deposition process resist corrosion by plasmas (such as fluorine plasma), and have a low vapor pressure to avoid contaminating the chip surface.
High-end instruments: Ion source electrodes (Ta-10Ti) for mass spectrometers and spectrometers. The high conductivity and high thermal resistance ensure the stable operation of the instruments in high vacuum and high temperature environments.
