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Titanium Alloy. Titanium and its alloys have proven to be technically superior and cost-effective materials of construction for a wide variety of aerospace, industrial, marine and medical applications.
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Titanium Alloy • Titanium and its alloys have proven to be technically superior and cost-effective materials of construction for a wide variety of aerospace, industrial, marine and medical applications. • In North America, approximately 70% of the titanium consumed is utilized for aerospace applications. • Due to the expansion of existing applications and the development of new uses, the greatest growth will occur in the industrial, marine and commercial sectors.
Titanium Alloy • Titanium is a white metal, and has the best strength to weight ratio among the metals. • Titanium is very reactive, and because of this it is often used for alloying and deoxidizing other metals. • Titanium is a more powerful deoxidizer of steel than silicon or manganese.
Titanium Alloy • Titanium is 40% lighter than steel and 60% heavier than aluminum. • This combination of high strength and low weight makes titanium a very useful structural metal. • Titanium also features excellent corrosion resistance, which stems from a thin oxide surface film which protects it from atmospheric and ocean conditions as well as a wide variety of chemicals.
Titanium Alloy Grade • There are five grades of what is known as commercially pure or unalloyed titanium, ASTM Grades 1 through 4, and 7. • Each grade has a different amount of impurity content, with Grade 1 being the most pure. • Tensile strengths vary from 172 MPa for Grade 1 to 483 MPa for Grade 4.
Titanium Alpha Alloy • Titanium alpha alloys are alloys that typically contain aluminum and tin, though they can also contain molybdenum, zirconium, nitrogen, vanadium, columbium, tantalum, and silicon. • Alpha alloys do not generally respond to heat treatment, but they are weldable and are commonly used for cryogenic applications, airplane parts, and chemical processing equipment.
Titanium Alpha-Beta Alloy • Alpha-beta alloys can be strengthened by heat treatment and aging, and therefore can undergo manufacturing while the material is still ductile, then undergo heat treatment to strengthen the material, which is a big advantage. • The alloys are used in aircraft and aircraft turbine parts, chemical processing equipment, marine hardware, and prosthetic devices.
Titanium Alpha-Beta Alloy • The smallest group of titanium alloys, beta alloys have good hardenability, good cold formability when they are solution-treated, and high strength when they are aged. • Beta alloys are slightly more dense than other titanium alloys, having densities ranging from 4840 to 5060 kg/m3. • They are the least creep resistant alloys, they are weldable, and can have yield strengths up to 1345 MPa. • They are used for heavier duty purposes on aircraft.
Titanium Alloy Implants Market: • Titanium is a standard material for medical devices such as hip joints, bone screws, knee joints, bone plates, dental implants, surgical devices, pacemaker cases and centrifuges due to its total resistance to attack by body fluids, high strength and low modulus.
Titanium Alloy Implants Metal of choice: • The body readily accepts titanium since it is more biocompatible than stainless steel or cobalt chrome. Titanium also has a higher fatigue strength than many other metals. The unique qualities of titanium prove to be MRI (Magnetic Resonance Imaging ) and CT (Computed Tomography ) compatible.
Titanium Alloy Implants Machinability: • The machinability of titanium is comparable to most stainless steels and better than cobalt chrome. Sharp, clean tools with good chip removal and ample coolant are recommended when Drilling, Turning, Milling or Cold Sawing titanium. The work hardening rate for titanium is less than stainless steel.
Titanium Alloy Implants Medical Specifications for Titanium Alloy: ASTM F-67-68(94)E1 Unalloyed titanium for surgical implant applications. ASTM F-136-92E1 Wrought titanium 6Al-4V ELi Alloy for surgical implant applications ASTM F 1472-93 Wrought titanium 6Al-4V Alloy for surgical implant applications.
Titanium in Medical Applications Bone and Joint Replacement: • About one million patients worldwide are treated annually for total replacement of arthritic hips and knee joints. • The prostheses come in many shapes and sizes. • Hip joints normally have a metallic femoral stem and head which locates into an ultrahigh molecular weight low friction polyethylene socket, both secured in position with polymethyl methacrylate bone cement.
Titanium in Medical Applications Bone and Joint Replacement: • Some designs, including cementless joints, use roughened bioactive surfaces (including hydroxyapatite) to stimulate osseointegration, limit resorption and thus increase the implant lifetime for younger recipients. • Internal and external bone-fracture fixation provides a further major application for titanium as spinal fusion devices, pins, bone-plates, screws, intramedullary nails, and external fixators.
Titanium in Medical Applications Dental Implants: • A major change in restorative dental practice worldwide has been possible through the use of titanium implants. • A titanium 'root' is introduced into the jaw bone with time subsequently allowed for osseointegration. • The superstructure of the tooth is then built onto the implant to give an effective replacement.
Titanium in Medical Applications Cardiovascular devices: • Titanium is regularly used for pacemaker cases and defibrillators, as the carrier structure for replacement heart valves, and for intra-vascular stents.
Titanium in Medical Applications External Prostheses: • Titanium is suitable for both temporary and long term external fixations and devices as well as for orthotic calipers and artificial limbs, both of which use titanium extensively for its light weight, toughness and corrosion resistance.
Titanium in Medical Applications Surgical Instruments: • A wide range of surgical instruments are made in titanium. • The metal's lightness is a positive aid to reducing any fatigue of the surgeon. • Instruments are frequently anodised to provide a non reflecting surface, essential in microsurgical operations, for example in eye surgery. • Titanium instruments withstand repeat sterilisation without compromise to edge or surface quality, corrosion resistance or strength. • Titanium is non magnetic, and there is therefore no threat of damage to small and sensitive implanted electronic devices.