Grade 5, 6-4 titanium has dominated the titanium discussion in manufacturing applications for decades, largely due to the extensive use of this workhorse alloy in military and advanced aerospace applications. grade 5 titanium abounds in the literature and is better known because it is traditionally the most commercially available titanium alloy. What is less well known is that while Grade 5 titanium is twice as strong as Grade 5 titanium, its low formability makes it twice as difficult to machine as Grade 9 titanium. While both alloys are excellent, Grade 5 titanium is not always the best titanium choice for cost effective precision production applications in the aerospace, automotive, medical, oil, gas and power generation industries.
Grade 9 titanium (3-2.5) is often the best choice for a wide range of applications in a variety of industries and is well suited for the production of high-tech products ranging from medical pacemakers to aerospace honeycombs.
The mechanical properties of Grade 9 titanium provide greater strength than commercially pure titanium. One of the main advantages of this titanium alloy containing 3% aluminum and 2.5% vanadium is that it can be cold worked, unlike Ti-6-4.
The result is good ductility, moderate strength and excellent corrosion resistance.
Grades 5 and 9 are both alpha-beta titanium alloys with 90% of the same alloy composition, but there are significant differences when considering production, labor and manufacturing costs. Both are high quality metals with excellent strength and corrosion resistance properties. Using Ti 6-4 when Ti 3-2.5 alloy can easily meet your component specifications will certainly have a negative impact on your bottom line. The application is always the deciding factor when choosing grade 5 or grade 9 titanium.
Welding either grade of titanium can be a difficult process requiring specific atmospheres and advanced techniques such as MIG, TIG, plasma arc and electron beam. nasa has a 217-page document, "Titanium and Titanium Alloy Welding Procedures," which details the current state of the art, including pre-weld cleaning, post-weld cleaning and operation, and joint design. The inherent manufacturing costs and technical precision required to use titanium make it imperative to use the most cost effective grade when the application allows, and for many applications the grade is Titanium 3-2.5.
While Titanium Grade 5 is slightly superior to Titanium Grade 9 in certain material properties such as shear and tensile strength, there are serious challenges in using it in manufacturing applications that use precision rolled coils.
Grade 5 titanium (Ti-6Al-4V) is a common choice for demanding applications, such as biomedical implants that require materials that can mimic bone and high temperature structural applications in the aerospace industry.
Vanadium is an important alloying element for Grade 5 and Grade 9 titanium. When alloyed with titanium, the resulting titanium alloy is much stronger than commercially pure titanium, while maintaining comparable stiffness and thermal properties. As mentioned earlier, Grade 5 has properties similar to those of human bone, making it a popular choice for orthopedic medical devices. Other more common applications include tension retaining rings, bicycle parts, and nuts and bolts for use in harsh conditions.
Typically titanium grade 5, also known as "6-4" in production shops, is used for applications involving machining. Titanium alloys are most commonly available only in sheet and plate, not in coil. Because Grade 5 is not cold formable, it cannot be stamped or drawn as effectively as Grade 9 titanium. It is most often used where forming is not required, as there are better options in formable titanium alloys. grade 5 can be thermoformed by contact heating, but requires special equipment and considerations that do not simplify the process as much as mass production when uncoiling from coils.
Grade 5 titanium is an excellent material and is well suited for very demanding applications. Higher values increase warehousing risks and storage costs for manufacturers due to the rising production and process costs of vacuum melting. Grade 5 must be carefully cut or ground to achieve the required thickness, and its use in small gauge applications is severely limited. As a result of these cutting and grinding operations, Grade 5 titanium scrap cannot be remelted after mixing with the grinding media, thus increasing yield losses.
This is why manufacturers of all grades in the 21st century are turning to Titanium 3-2.5 as a solution when their manufacturing applications require strip, foil or wire gauge.
At KLS Metal Clad Materials Company, we offer Grade 9 Titanium as a cold rolled, more viable alternative to its 6% aluminum, 4% vanadium cousin. (Just-In-Time) supply chain so prevalent in today's competitive layered manufacturing environment. Versatile Grade 9 Titanium 3Al-2.5V is available in wire, foil and strip coils and can be ordered on demand with short lead times to reduce the need for inventory in expensive storage facilities.
Grade 9, or simply TI 3-2.5 titanium, can be rolled to smaller gauges, making it more suitable for a wider range of parts and assemblies than Grade 5. Grade 9 titanium has excellent corrosion resistance and can be used at higher temperatures than commercial pure grades 1 through 4. Because it can be cold rolled and formed, Titanium 3-2.5 is well suited for precision applications in the medical, aerospace, marine and automotive industries, with easier processability and excellent corrosion resistance. Unlike Titanium 6-4, Grade 9 can be drawn, stamped and formed, and we can roll it to extremely thin gauges of 0.001 in. or 0.025 mm. Grade 9 can be heat treated, has good weldability and is much less difficult to form than Titanium 5, which can be cold worked and age hardened. Some common applications include:
● Tennis rackets
● Medical pacemakers
● Corrugated tubing
● Hydraulic oil hoses
● Golf club shafts
Grade 9 titanium is the optimal material solution for many engineers and manufacturers who are looking for a way to bridge the difficulty and cost gap associated with using commercially pure grade titanium and grade 5 titanium alloys. If you think Grade 9 titanium may be the metal of choice for your application, contact the experts at KLS Metal Clad Materials Company today for a consultation.
