Titanium Vs Aluminum, What is the Difference?
Nowadays, all industries are looking for innovative ways to maximize profits. These innovative methods are expected to reduce production costs, reduce product weight and reduce overall energy consumption. As a result, lightweight metals including titanium and aluminum are increasingly being considered as steel.
Therefore, in order to get the perfect material solution, it is important to know its strength information. This article compares the various properties of titanium and aluminum to let you know which material you need.
Let’s Compare 17 Differences Between Titanium and Aluminum
In the manufacturing space, when you think of a dream team of material properties for parts, strength and lightweight come to mind. In essence, titanium and aluminum naturally come to the mind of designers in this case. Interestingly, both titanium and aluminum tick off other important boxes such as excellent tolerance for heat and resistance to corrosion. To help obtain the perfect choice for your project, we will be using a variety of properties to draw a comparison between aluminum and titanium. They include:
Titanium vs Aluminum: Element Composition
To better differentiate between titanium and aluminum, it is important to understand their elemental composition. This is because different components have different reactivity with the environment or because they may add additional properties to the metal as a whole. These properties include corrosion resistance, weight, etc. Their elemental composition is as follows
Titanium contains a variety of elements, including nitrogen, hydrogen, oxygen, carbon, iron, and nickel. Titanium is the main elemental composition, and the composition of other components may vary from 0.013 to 0.5%.
Aluminum is composed of a variety of components, including silicon, zinc, magnesium, manganese, copper, iron, titanium, chromium, zirconium, etc., with aluminum as the main component.
Titanium vs Aluminum: Corrosion Resistance
Corrosion resistance is another property that can be used to draw comparisons between titanium and aluminum. Both titanium and aluminum feature excellent corrosion resistance properties. However, one is more resistant than the other and as a result, it is more preferable when corrosion resistance is one of the major considerations in a project.
Titanium is inert and as result, it is highly corrosion-resistant. Because of its inert nature, titanium is the most biocompatible metal with impressive application in the medical industry. This application may be found in the production of surgical applications while Ti 6-4 alloys hold up well in a salty environment with great application in the marine industry. On the other hand, alloys of aluminum form a layer of oxides that makes the material non-reactive with corrosive elements. However, the corrosion of such alloy now depends on the aqueous/atmospheric conditions such as temperature, airborne chemicals, and chemical composition.
Titanium vs Aluminum: Electrical conductivity
Conductivity refers to the ability of a material to allow electrons to flow when the potential drops. To determine the conductivity of a material, copper is used as a standard for assessing conductivity.
When comparing the conductivity of titanium to copper, titanium has a conductivity of about 3.1% of copper and aluminum has a conductivity of 64% of copper. Titanium has relatively poor conductivity and high resistivity, which means that titanium can be used as a good resistor.
This makes titanium alloys excellent in applications that require high anti-magnetism, such as magnetic resonance imaging and maglev trains. Although aluminum alloys have a certain degree of conductivity, they are more suitable for applications that require moderate anti-magnetism and high conductivity, such as electronic equipment and communication equipment, compared to titanium alloys.
Titanium vs Aluminum: Thermal Conductivity
The thermal conductivity of a material is its ability to transfer or conduct heat. For a material to be a good radiator it must have a high rate of conductivity while a material with low thermal conductivity is a good insulator. This phenomenon is referred to as the time rate of transfer by conduction through the unit thickness, across a unit of material for a unit temperature gradient.
In comparison, aluminum has a high thermal conductivity of 1460 BTU-in/hr-ft²-°F (210 W/m-K) compared to titanium 118 BTU-in/hr-ft²-°Fm (17.0 W/m-K). This is why it is given preferential treatment when it involves applications including heat exchangers, cookware, and heatsinks.
Titanium vs Aluminum: Melting point
A metal’s melting temperature known as the melting point is the temperature at which such metal begins to transit from a solid phase into a liquid phase. At this temperature, the solid phase of the metal and the liquid phase of such metal exist in equilibrium. Once the material reaches this temperature level, it can be easily formed and it can be used for thermal applications.
In comparison, titanium has a higher melting point of 1650 – 1670 °C (3000 – 3040 °F) which is why it is used as a refractory metal. On the other hand, aluminum exhibit a lower melting point compared to titanium 660.37 °C (1220.7 °F). Therefore, in a heat resistance application titanium is more applicable.
Titanium vs Aluminum: Hardness
A metal’s hardness is its comparative value which helps to describe its response to etching, denting, deformation, or scratching along its surface. This can be mostly done with a tool called an indenter machine. As a result, the indenter machine or tools brings out the value of the metal to determine the strength of such metal. While the Brinell’s hardness of titanium 70 HB is greater than pure aluminum 15 HB, some alloys of aluminum exhibited higher hardness than titanium. Examples include AA7075 temper T7 & T6, AA6082 temper T5 & T6, and more.
On the other hand, titanium deforms easily when scratched or indented. This can be corrected because titanium forms an exceptionally hard surface by forming an oxide layer to form a titanium oxide layer that resists most penetration forces. In an application where hardness is one of the major requirements, then, titanium is the best choice.
Titanium vs Aluminum: Density
The density of titanium alloy is 4.54g/cm³, while the density of aluminum alloy is 2.7g/cm³. Aluminum alloys are widely used in automobiles, bicycles, and airplanes where weight reduction is required due to their lightweight characteristics.
Although titanium alloys are heavier than aluminum alloys, the specific strength of some high-strength titanium alloys is much greater than that of other metal structural materials, and their lightweight properties still make them ideal for high-performance applications such as spacecraft and medical devices.
Titanium vs Aluminum: Price
Generally speaking, titanium alloys cost much more than aluminum alloys. This is because titanium alloys have a higher melting point, are more difficult to process, and titanium ore resources are relatively scarce.
Aluminum is the most cost-effective metal for machining or 3D printing; titanium costs more, but it can still drive a leap in value. Lightweight parts will bring huge benefits to aircraft or spacecraft in terms of fuel savings, while titanium alloy parts have a longer service life.
Titanium vs Aluminum: Durability
The durability of material remains its ability to be functional without the use of excessive repairs or maintenance when the material is acted upon by challenges of normal operations. No doubt, both titanium and aluminum are durable and can be used for a longer period. Titanium is very rigid and durable and its frames can last for decades without any sign of wear and tear when is properly cared for.
Also, titanium provides reasonable flex to help deaden the vibration of the road and can feel whippy when exposed to a heavy load like touring panniers. On the other hand, aluminum also proves its durability in extreme transportation environments especially when strength, safety, and durability are critical.
Titanium vs Aluminum: Machinability
Machinability is a comparative score of a metal to determine how well they react to machining stress including stamping, turning, milling, and many more. The machinability score of such metal is used to determine the type of machining method to be used. Interestingly, CNC turning and milling are time-tested methods of producing titanium and aluminum parts. They can be produced in less than a day with adherence to tolerances of +/-0.005 mm. When the production of parts is required quickly, aluminum is a perfect choice since it is cost-effective with high quality.
However, machining may be somewhat limited when it comes to geometrics because extremely complex designs require a different solution irrespective of the chosen material. Another factor to consider when choosing material for machining is machining waste. Hence, milling away excess material is fine for inexpensive aluminum but not ideal for costly titanium. As a result, manufacturers often prefer to produce prototypes using aluminum, then later switch to titanium for parts production.
Titanium vs Aluminum: Formability
In terms of formability, aluminum is more formable than titanium. All forms of aluminum are readily fabricated into finished parts using a wide variety of methods. Aluminum can be cut using many processes depending on the form and shape of the material.
It can also be cut with different types of saw while laser, plasma, or water jet produce finished sizes that can have intricate forms and shapes. While titanium is formable and not as formable as aluminum, aluminum is the perfect choice when formability is critical for the success of a project.
Titanium vs Aluminum: Weldability
When it comes to welding which is the ability of a material to welded, both metals can be welded and they can also be welded or joined together. However, either titanium or aluminum is more weldable than the other.
In comparison, titanium welding requires more professionalism as it is always regarded as a specialty within a specialty. On the other hand, aluminum is highly weldable and it is used for a wide range of applications. So, if weldability is one of the major requirements for material selection, aluminum will be a perfect choice.
Titanium vs Aluminum: Yield Strength
The yield strength of a material is the maximum stress at which a material begins to permanently deform. This property can be used to differentiate titanium from aluminum. When compared, it is evident that commercially pure titanium (> 99% Ti) is a low-to-moderate strength metal that is not well suited for structures or engines of aircraft. It exhibits the yield strength of high-purity titanium ranging from 170 MPa up o about 480 MPa which is regarded low for heavily loaded aerostructures.
On the other hand, pure aluminum exhibits a yield strength ranging from 7 MPa up to about 11 MPa while alloys of aluminum exhibit a yield strength ranging from 200 MPa up to 600 MPa.
Titanium vs Aluminum: Tensile strength
The tensile strength of a metal is the highest (ultimate) on the curve of engineering stress-strain. This is termed the highest stress that may be sustained when a material is exposed to tension. The ultimate tensile strength at an ambient temperature of titanium and its alloys ranges from 230 MPa for the softest grade of commercially pure titanium to 1400 MPa for high strength alloys.
Also, the proof strengths of titanium vary from around 170 MPa to 1100 MPa based on grade and condition. On the other hand, alloys of aluminum exhibit far greater strength than pure aluminum. Pure aluminum exhibit a tensile strength of 90 MPa and can be increased to over 690 MPa for some heat-treatable alloys of aluminum.
Titanium vs Aluminum: Shear Strength
The resistant properties of metal against the shear load before the component fail in shear is referred to as shear strength. This majorly occurs normally on a plane in a parallel direction to the direction of the force acting. Titanium shear stress is rated between 40 to 45 MPa depending on alloy properties while the shear strength of aluminum is rated between 85 to about 435 MPa. Therefore, if shear strength constitutes one of the major reasons for material selection, some grades of aluminum may be preferable over titanium.
Titanium vs Aluminum: Color
In differentiating or telling a difference between titanium and aluminum, the color of the material is important. This will help to recognize the material to avoid using the wrong metal for your project. To differentiate, aluminum has a silvery-white appearance that varies in color from silver to dull grey depending on the material’s surface. This appearance is normally towards silver for smooth surfaces. On the other hand, titanium has a silver appearance which is darker when viewed under the light.
Titanium vs Aluminum: Applications
Titanium and aluminum are both used in a vast varieties of applications. These applicable constitutes possible way to differentiate both metals from one another. The application of titanium and alumium is as stated below:
Titanium
Titanium is applicable in various ways out of which include as an alloying element in steel, reduces grain size, and as a deoxidizer and in stainless steel to reduce carbon content. It is found almost everywhere in the industrial space including:
- Pigments, coating, and additives (paints, toothpaste, paper, & plastic)
- Marine& Aerospace (landing gear, firewalls, critical structurer parts, hydraulic system,
- Industry (valves, process vessel, heat exchanger, tanks, pulp & paper industry, ultrasonic welding, sputtering targets, and many more.
- Consumer & architectural (sporting goods, spectacle frame, bicycles, firearms, shovels, laptop parts, and many more
- Jewelry (for body piercing, watch, rings, and many more)
- Medical (dental implants, surgical instruments, surgical implements, and more
Aluminum
Aluminum is generally used in different industries due to the impressive corrosion resistance it offers. Aluminum exists in varieties of alloys which markedly improves its mechanical properties, especially when tempered. For example, the most common aluminum alloy in form of foils and beverage cans arranges from 92% to about 99% aluminum. The major application of aluminum include:
- Transportation (aircraft, railways cars, bicycles, automobiles, trucks, marine vessels, spacecraft, and many more)
- Packaging (cans, frame, foils,)
- Building & Construction (windows, siding, roofing, doors, building wire, sheathing, and many more)
- Electricity-related applications (motor, transformers, generators, conductor alloys, generators, and many more)
- Household Items (cooking utensils, furniture, and many more)
- Equipment & Machinery (pipes, tools, processing equipment, and many more)
Summary
By comparing 17 properties of titanium and aluminum, including elemental composition, corrosion resistance, conductivity, etc., I believe you have a basic understanding of the choice between titanium and aluminum. If you are still undecided about which material to choose for your project, please contact us immediately. We have a professional engineering team that can solve your problems at any time.
