Metals and their alloys are commonly used to manufacture products due to their strength, durability, conduction, and ductility. Titanium and stainless steel are two such metals we commonly utilize to make objects that require longevity, toughness, and inertness. Although they hold similar properties, some key differences between the two affect their individual industrial applications.
If you’re wondering which one to choose over the other for your project, let us help. In this article, we have comprehensively analyzed both titanium and stainless steel against each other to assist you.
Understanding Steel and Titanium
Titanium is a pure metal – an element in the periodic table. Commercially, it often contains impurities like carbon, nitrogen, oxygen, hydrogen, and even iron in low percentages. These are ideally less than 0.5%, but their presence classifies titanium into multiple grades with varying applications. The purest of these grades include:
- Grade 1 is the purest form of titanium, containing 99.5% or higher percentages of the element.
- Grade 2 titanium typically contains 99% of the element, along with a small amount of oxygen.
- Grade 3 titanium contains 0.3% molybdenum and 0.8% nickel.
- Grade 4 titanium contains 0.5% molybdenum.
Stainless steel is an alloy of multiple metals and carbon. Depending on its grade and corrosion resistance, it can have around 8% or more nickel, 10.5% chromium, and 1.2% carbon.
As there are near-infinite ways to alter the composition of an alloy like stainless steel and altering the said composition alters properties, this alloy comes with its own classification system. This allows you to easily identify the materials used in manufacturing the stainless steel. These grades and series include the following:
- The 200 series contains chromium-nickel-manganese alloys.
- The 300 series contains chromium-nickel alloys.
- The 400 series contains ferritic and martensitic chromium alloys.
- The 500 series contains heat-resistant chromium alloys
- The 600 series contains martensitic alloys
- Type 102 is austenitic.
- Type 2205 contains both ferritic and austenitic iron.
- Type 2304 also contains ferritic and austenitic iron but with a lower molybdenum content.
All these series have different industrial applications.
Comparing the Properties of Titanium and Stainless Steel
The properties of stainless steel depend immensely on its composition, and the properties of titanium vary considerably with its purity. Let’s compare the general properties of the two materials:
A material’s hardness refers to its resistance against deforming forces. The quality depicts the strength of its surface against penetration, dents, scratching, and indentation. Stainless steels are generally tougher than titanium, although titanium has a natural layer of titanium oxide on its surface that helps it resist deforming forces.
2. Thermal Conductivity and Melting Points
Titanium is generally preferred over stainless steel in projects that require thermal stability at high temperatures. It conducts heat better and melts at 1,668°C in its pure form, in comparison to stainless steel’s 1400-1500°C.
3. Corrosion Resistance
Corrosion resistance refers to the ability of a material to resist chemical reactions with its environment and environmental components, like moisture, acids, oxygen, etc.
The kind and percentage of components in stainless steel can be modified considerably to enhance its resistance to corrosive forces. However, it still loses against titanium by a significant margin.
A strong and stable oxide layer naturally protects titanium’s surface, whereas stainless steel relies on its thin chromium oxide layer that can be broken down over time, especially if exposed to harsh chemical environments. As a result, titanium is considered more stable in industrial applications involving harsher or more humid environments.
4. Strength, Weight, and the Strength-to-Weight Ratio
A material’s weight is often vital when considering its industrial application. Titanium weighs around 40% less than stainless steel. And it has a higher strength-to-weight ratio, allowing it to perform better with less weight. Its yield strength is generally higher than stainless steel as well, making it excellent in applications that require low weight but high strength, like military and aerospace projects. However, a comprehensive comparison between the two reveals titanium to be weaker, especially in terms of tensile strength.
Both titanium and stainless steel are excellently durable.
Titanium has a strong oxide film on its exposed surface. The layer is inert and makes the metal more durable, unreactive, and long-lasting than stainless steel in terms of its chemical stability. This also makes the metal more stable and tolerant of higher temperatures than stainless steel, which loses its strength as temperatures fluctuate. It’s less prone to fatigue and shattering as well.
6. Electrical Conduction
Stainless steel is a better conductor of electricity than titanium, as the latter has a higher resistivity. Both these products can be used as conductive materials, depending on the environment, cost, and strength demands. Stainless steel is commonly used in wiring, whereas titanium finds its applications in electronic components like capacitors, piezoelectric transducers, etc.
7. Elasticity, Flexibility, Malleability, and Ductility
All these properties indicate how easily a material can be shaped, rolled, stretched, formed into wires, and flattened without breaking or cracking. Stainless steel wins in this regard, and it can take high stress and strain to deform without cracking or losing its structural integrity. Titanium, on the other hand, is more prone to cracking or breaking and is not easy to work with, especially where high stress and strain are involved.
Machining entails using precision machines to cut an object to a desired shape and size. The industrial metal fabrication processing of stainless steel is significantly easier and more economical to machine than titanium.
Titanium readily reacts with gasses in the air, like oxygen and nitrogen, to form brittle oxides on its surface; you have to use special fluids during the machining process to remove the oxides. Additionally, the material’s high strength-to-weight ratio and low ductility make it hard to process.
9. Toxicity and Biocompatibility
Both materials are generally non-toxic and bio-compatible, although stainless steel typically contains small amounts of nickel and other elements, which can cause allergic reactions in some individuals. Although stainless steel, in general, is treated as sufficiently biocompatible.
Titanium is non-toxic, non-allergenic, and biocompatible. And as it is more resistant to corrosion and wear compared to stainless steel, it does not release metal ions into the surrounding tissues when implanted. One of the most important and fascinating properties of titanium includes its ability to promote the integration of bone and implant (osseointegration). It also has a low inflammatory response.
There are subtle yet noticeable aesthetic differences between titanium and stainless steel, which can affect their industrial use. Stainless steel is more reflective with a bright, shiny, polished finish. It also can be modified to have brushed, satin, or matte finishes that look industrial.
On the other hand, titanium’s distinct satin-like finish is not as reflective as stainless steel and is often referred to as ‘gun-metal’ and space-age. It can be anodized to produce multiple colors, ranging from blue, purple, and green to gold.
The cost comparison of titanium and stainless steel is straightforward: titanium has always been more expensive than steel. As of early 2023, it costs 4 to 5 times more than stainless steel. This is because of multiple reasons:
- Titanium is rarer than iron.
- The extraction process of titanium is more complex and energy and resource intensive than iron – the major component of stainless steel.
- Machining titanium costs around 30 times more than machining steel.
Using Titanium and Stainless to Manufacture Products Industrially
The industrial applications of titanium and stainless steel vary considerably per project. Large-scale projects that require high strength and liberal material use often use stainless steel, as it is much less expensive, easy to process, offers considerable strength, is corrosion-resistant, and has superior hardness. However, projects that require high yield strength, strength-to-weight ratio, high stability against corrosion and temperature, and biocompatibility use titanium.
Let’s discuss some typical applications of these two materials.
Titanium is commonly used in the following industries:
1. The Medical Industry
Titanium’s high strength-to-weight ratio, superior corrosion resistance, and non-toxicity and biocompatibility make it excellent to use for medical implants and devices. Common titanium objects in the industry include the following:
- Dental implants
- Making artificial joints for joint replacements
- Bone plates and screws
- Pacemaker casings
- Surgical instruments like bone saws
- Other medical equipment like wheelchairs and crutches
2. The Aerospace and Marine Industry
Titanium’s low weight and high melting point, strength, and durability have found numerous uses in the aerospace industry. It’s used to make the following:
- Aircraft frames
- Propeller shafts
- Ship hulls
- Ballast tanks
- Underwater equipment
- Aircraft engine components like compressor and fan blades,
- Landing gear that can withstand high impact
- Fasteners that hold multiple components together
- Heat exchangers in aircraft engines, the marine industry, and environmental control systems
3. Chemical Processing and Power Generation
Titanium’s high corrosion resistance and melting point make it ideal to be used in extreme environments like the ones in the chemical and power industry. Some of the main applications include the following:
- Reaction vessels
- Components in desalination plants
- Turbine blades
- Reactor components
- Condenser tubes
4. Sports, Construction, and Architecture
Titanium’s strength and unique aesthetic appeal have made it popular for decorative and functional use in sports and architecture. It’s used in the following:
- Cladding in building facades
- Bicycle frames
- Golf club heads
- Interior design components like wall panels and ceiling tiles
- Structural building components
Stainless steel is a popular industrial material choice due to its high durability, low cost, and considerable strength. Some industries that employ it include:
1. The Construction Industry
The construction industry widely uses stainless steel in the following:
- Structural frames
- Roofing and cladding
- Handrails and balustrades
- Elevator interiors
- HVAC systems
2. The Medical Industry
Stainless steel is relatively inexpensive, yet it offers durability and corrosion resistance for use in medical applications like
- MRI machines
- Catheters and needles
- Dental and surgical instruments
3. Energy Industry
Here, stainless steel is used to make major components of power generation equipment like the following:
- Heat exchangers,
- Fuel cladding,
- Nuclear reactor vessels
4. The Automotive Industry
In the automotive industry, you’ll find stainless steel in the following components due to its durability:
- Exhaust systems
- Fuel tanks
- Brake components
- Suspension systems
- Decorative vehicle trims
Verdict: Which Metal is Superior: Titanium or Stainless Steel?
As we discussed in the article, you can use both materials interchangeably in many cases, except if your project is exposed to harsher environments.
The strength and durability comparison of titanium and stainless steel isn’t as straightforward as steel is harder and stronger when faced with tensile forces, whereas titanium has a high yield strength and is less prone to fatigue. And titanium has a higher per-unit strength in terms of weight; if two projects require the same strength, the one made of titanium will weigh less than the one made of stainless steel.
Objects that are relatively smaller and have to be placed in highly humid, chemically harsh, or biologically sensitive environments are best made with titanium. If you’re not concerned with adding weight to your project, and need a hard material placed in a suitable environment, you can use stainless steel.
Your project’s budget will also affect your choice of metal. Titanium is costly to obtain and process. In comparison, you can obtain stainless steel economically and get it machined easily. However, properties like corrosion resistance can not be helped.
Overall, it’s best not to choose one metal over the other in general when comparing titanium and stainless steel, as different projects have varying requirements, budgets, and environments. Make sure you assess all the properties and qualities your project requires before deciding on a metal.
No matter what metal you end up choosing, we can work with it for your projects. Contact us for a quote.