Types of Materials an Exhaust System Can Be Made From (Pros & Cons)
Updated: Jan 9
Exhaust systems are a crucial component of vehicles, as they are responsible for directing exhaust gases away from the vehicle and its occupants. These exhaust systems can be made from a variety of materials, each with their own unique properties and characteristics.
In this article, we'll discuss the different types of materials an exhaust system can be made from, as well as the pros and cons the materials.
Table of Contents:
Steel
One common material used in exhaust systems is steel. Steel is a durable and strong metal that is able to withstand the high temperatures and pressures generated by the exhaust gases. It is also relatively inexpensive, making it a popular choice for manufacturers.
Steel can withstand heat of around 540 ℃ for a short time.
Advantages
There are several advantages to using steel in exhaust systems compared to other materials.
Strength and durability. Steel is able to withstand the high temperatures and pressures generated by the exhaust gases, making it a reliable and long-lasting material for this application.
Affordability. Another advantage of steel is its affordability. Steel is generally less expensive than other materials such as stainless steel or aluminum, making it a cost-effective choice for manufacturers.
Easy to work with. Steel is easy to work with and can be molded into a variety of shapes and sizes. This makes it a versatile material that can be used in a wide range of exhaust system designs.
The durability, affordability, and versatility of steel make it a popular choice for exhaust systems. These advantages make it a reliable and cost-effective material for this application.
Disadvantages
While there are several advantages to using steel in exhaust systems, there are also some disadvantages to consider.
Can rust easily. Steel is not as corrosion-resistant as some other materials. Over time, the high temperatures and chemical reactions of the exhaust gases can cause steel to rust and corrode, which can lead to exhaust leaks and other issues.
Heavy. Steel is relatively heavy compared to other materials. This added weight can negatively impact the vehicle's fuel efficiency and performance. In addition, the added weight can put additional strain on the vehicle's suspension and other components.
Although some steel exhausts are zinc coated or hot dipped in aluminium, which helps in corrosion prevention, a mild steel exhaust will simply be more exposed to the elements and will rust.
While steel has some advantages as a material for exhaust systems, its potential for corrosion and added weight are disadvantages to consider. These factors may make other materials, such as stainless steel or aluminum, a better choice for some applications.
Stainless Steel
Another material commonly used in exhaust systems is stainless steel. This type of steel offers even greater durability and corrosion resistance, making it a good choice for high-performance vehicles or vehicles that are frequently exposed to harsh weather conditions.
Stainless steel is a corrosion-resistant alloy metal manufactured from iron and 10-20% chromium. There are many grades of stainless steel, grade 409 is the most common.
Stainless steel with a chromium content of 18% can withstand heat of around 870 ℃.
Advantages
Stainless steel is a better version of generic steel while still being more affordable than more exotic materials.
Durability. Stainless steel is used in exhaust systems due to its increased durability and corrosion resistance compared to other materials. While usually not as strong as generic steel, its still very strong.
Corrosion resistance. Stainless steel is able to withstand the high temperatures and chemical reactions of the exhaust gases without rusting or corroding, making it a long-lasting and reliable material for this application.
Lighter weight. Stainless steel is lighter than generic steel, which can help improve the vehicle's fuel efficiency and performance. In addition, the reduced weight can put less strain on the vehicle's suspension and other components.
Affordable compared to other materials. Stainless steel is a relatively affordable material compared to other options such as aluminium or titanium. This makes it a cost-effective choice for manufacturers while still providing the benefits of increased durability and corrosion resistance.
The increased durability, corrosion resistance, and weight-saving properties of stainless steel make it a popular choice for exhaust systems. These advantages make it a reliable and cost-effective material for this application.
Disadvantages
While there are several advantages to using stainless steel in exhaust systems, there are also some disadvantages to consider.
Not as strong as generic steel. Stainless steel is very strong but may not be as strong as other materials such as generic steel. This can make it less suitable for applications where extreme strength and durability are required.
Not completely resistant to corrosion. Stainless steel is not completely resistant to corrosion. While it is more resistant than regular steel, it can still corrode over time if exposed to certain conditions. This can reduce its effectiveness in some situations.
More expensive. It is still relatively affordable but is still more expensive than regular steel.
While stainless steel has some advantages as a material for exhaust systems, its potential for reduced strength and heat resistance are disadvantages to consider.
Aluminium
Aluminium is another material that is sometimes used in exhaust systems. It is lighter than steel, which can help improve the vehicle's fuel efficiency. However, it is not as strong or durable, so it is typically used in combination with other materials to provide the necessary strength and durability.
Aluminium can withstand heat of around 600 ℃.
Advantages
Aluminium is sometimes used in exhaust systems where weight reduction is sought after.
Lightweight. One of the main advantages of using aluminium in exhaust systems is its light weight. Aluminum is much lighter than steel or stainless steel, which can help improve the vehicle's fuel efficiency and performance. In addition, the reduced weight can put less strain on the vehicle's suspension and other components.
Affordable. Aluminium is a relatively affordable material compared to other materials. This makes it a cost-effective choice for manufacturers while still providing the benefits of reduced weight.
Excellent corrosion resistance. The aluminium oxide coating is highly resistant to corrosion and renews itself if damaged. It has the highest corrosion resistance in its natural condition, pure or 1xxx aluminium, but this property is weakened when alloys (copper and iron but also magnesium or zinc) are added.
The lightweight properties of aluminium while still being affordable, its corrosion and heat resistance make it a popular choice for exhaust systems. These advantages make it a reliable and cost-effective material for this application.
Disadvantages
While there are several advantages to using aluminium in exhaust systems, there are also some disadvantages to consider.
Not as strong. One disadvantage is that aluminium is not as strong as other materials such as steel or stainless steel. This can make it less suitable for applications where extreme strength and durability are required.
Not immune to heat damage. Aluminium is not immune to heat damage, while it has good heat resistance, it can still deform or melt under extreme conditions. This can reduce its effectiveness as an exhaust system material in extreme heat situations.
While aluminium has some advantages as a material for exhaust systems, its potential for reduced durability are disadvantages to consider. These factors may make other materials, such as steel or stainless steel, a better choice for some applications.
Titanium
Titanium is a relatively new material that is being used in some exhaust systems due to its unique properties and advantages over other materials.
Aluminium can withstand heat of around 600 ℃.
Advantages
Titanium is a more exotic material used in exhaust systems, it has several advantages over other materials.
Strength and durability. One of the main advantages of using titanium in exhaust systems is its strength and durability. Titanium is one of the strongest and most durable metals, which makes it a reliable and long-lasting material for this application.
Lightweight. Another advantage of titanium is its low density. It is much lighter (about 40% lighter than steel) than other materials such as steel or aluminium, which can help improve the vehicle's performance. In addition, the reduced weight can put less strain on the vehicle's suspension and other components.
Heat and corrosion resistant. In addition, titanium has good heat resistance and corrosion resistance. It is able to withstand the high temperatures and chemical reactions of the exhaust gases without deforming or corroding, making it a reliable material for this application.
The strong, lightweight, and corrosion-resistant properties of titanium make it an attractive material for exhaust systems. These advantages make it a reliable material for this application.
Disadvantages
While there are several advantages to using titanium in exhaust systems, there are also some disadvantages to consider.
High cost. Titanium is a relatively expensive material compared to other options such as steel or aluminium. This can make it less cost-effective for manufacturers and consumers.
Not immune to heat damage. While titanium has good heat resistance, it can still deform or melt under extreme heat conditions. This can reduce its effectiveness as an exhaust system material.
Not immune to corrosion. Titanium is not immune to corrosion. While it is more resistant than other materials, it can still corrode over time if exposed to certain conditions. This can reduce its effectiveness as an exhaust system material.
While titanium has some advantages as a material for exhaust systems, its high cost and potential for heat damage and corrosion are disadvantages to consider. These factors may make other materials a better choice for some exhaust system applications.
Nickel Alloys (Inconel)
Inconel is a nickel alloy that is sometimes used in exhaust systems due to its unique properties and advantages over other materials.
Inconel is an alloy mostly composed of nickel and chromium. Its strength and high melting point make it attractive in the aerospace and nuclear energy industries.
Inconel alloy 625 can withstand heat of up to 982 ℃.
Advantages
Inconel alloy is an exotic material not commonly used in exhaust systems, it does have some unique advantages when compared to other materials.
Excellent heat resistance. One of the main advantages of using Inconel in exhaust systems is its excellent heat resistance. It is able to withstand the high temperatures of the exhaust gases without deforming or melting, making it a reliable material for this application.
Excellent corrosion resistance. Another advantage of Inconel is its corrosion resistance. It is able to withstand the chemical reactions of the exhaust gases without rusting or corroding, making it a long-lasting and reliable material for this application.
Strength and durability. Inconel is a strong and durable metal. It is able to withstand the high pressures and stresses of the exhaust gases, making it a suitable material for high-performance vehicles or applications where extreme strength and durability are required.
The excellent heat resistance, corrosion resistance, and strength of Inconel make it a popular choice for exhaust systems. These advantages make it a reliable and cost-effective material for this application.
Disadvantages
While there are several unique advantages to using Inconel in exhaust systems, there are also some disadvantages to consider.
High cost. One disadvantage is the cost. Inconel is a relatively expensive material compared to other options such as steel or aluminium. This can make it less cost-effective for manufacturers and consumers.
Quite heavy. In addition, Inconel is a relatively heavy metal. While it is stronger and more durable than other materials, the added weight can negatively impact the vehicle's performance. The added weight can put additional strain on the vehicle's suspension and other components.
While Inconel has some advantages as a material for exhaust systems, its high cost and potential for heat damage and added weight are disadvantages to consider. These factors may make other materials, such as steel or stainless steel, a better choice for some applications.
Which Type of Material Is Best for an Exhaust System?
The choice of materials used in an exhaust system depends on the specific needs and requirements of the vehicle. Manufacturers and consumers must carefully consider the following factors when designing or choosing an exhaust system.
Application. Will it be exposed to extreme heat or water, will it be used for automotive or marine environments, or will it be used for the exhaust manifold or just the tail pipes, these are examples of questions you should be asking in regards to the material you require for an exhaust system.
Strength and durability. Will it be subject to damage or high stresses?
Corrosion resistance. Will the exhaust system be subject to water, salt or other corroding chemicals and environments?
Heat resistance. Will the exhaust be subject to extreme heat?
Cost. How expensive should the exhaust system be?
Weight. Some materials are lighter and heavier than others.