In the world of metal materials, alloy steel, carbon steel and stainless steel each occupy an important position with their unique properties and application fields. However, when it comes to the property of “sturdiness,” people often wonder: Which type of steel is stronger? In order to answer this question, we need to delve into the strength comparison, composition, characteristics and application scenarios of these three steels.
What is Alloy Steel?
All steel products are, by definition, alloys. (An “alloy” is simply a substance made from two or more metals.) Steel is an alloy because it’s a mixture of iron and a small percentage of carbon.“Alloy steel” however, is a steel that has been mixed with additional properties, which may include manganese, nickel, chromium, or boron, among many others. It is strong, hard, and generally tough, and it can usually resist wear and damage better than other steels.
Usually alloy steels are divided into two subcategories: low and high alloy. Low alloy has less than 8% of other elements, and they often have better hardness and are resistant to wear. However, high alloy steels usually have better tensile strength.
Types of Alloy Steel
Here are the categories under which alloy steel types are classified:
High-Alloy Steels
These alloy steels usually contain a high amount (more than 5% of the total composition) of one or more alloying elements for excellent toughness, hardness, and strength. Common alloying elements for this alloy steel category include manganese, chromium, vanadium, nickel, and molybdenum. Stainless steel is a perfect example of high-alloy steel, containing a minimum of 12% chromium, depending on its grade.
Low-Alloy Steels
Low-alloy steels contain a lower portion of one or more alloying elements (maximum of 5% of the total composition), offering improved toughness, strength, hardness, or other qualities. Typical examples of alloying elements in this category include tungsten, molybdenum, copper, chromium, manganese, boron, and nickel. Further, typical applications for low-alloy steels include mining and construction equipment due to their high requirement for good strength-to-weight ratios properties.
Maraging Steels
These steels are famous for their superior toughness and strength. Manufacturers find a use for these steels in applications that require high-strength properties, including military and aerospace applications.
Tool Steels
Tool steels are commonly known as highly alloyed steel suitable for tool and die applications in particular. Tool steels can resist wear and hardness even when exposed to high temperatures.
Common applications for Alloy Steel
- Aerospace: Their high strength-to-weight ratio makes them suitable for constructing aircraft engines and other components.
- Automotive: Alloy steel is capable of withstanding tough conditions, making it a desirable material for various purposes. They are applied in the automotive industry in making components like gears and axles.
- Energy: Alloy steel is resistant to high temperature and pressure thus, suitable for use in energy and power generation as steam turbines, pressure vessels, and boilers.
- Heavy machinery: Given their high wear resistance, strength, and toughness, they are used in the manufacturing of heavy machineries like crusher jaws and drillers.
What is Carbon Steel?
Carbon steel is an alloy that combines iron and a high percentage of carbon. As we discussed above, all steel is an alloy of iron and carbon, but what is known as “carbon steel” in the industry simply has more carbon content than other steel.
In this category, there are low-carbon steel and high-carbon steel. Low-carbon steel is strong and tough, and it can be case-hardened when required. High-carbon, on the other hand, can be heat-treated to make it much harder. But when heated, it becomes more brittle, so it may not fit all applications and it can be difficult to work with.
Types of Carbon Steel
| Types of Carbon Steel | Amount of carbon | Properties |
| Low carbon steel, also called mild carbon steel | Maximum of 0.3% | Low hardness and cost. High ductility, toughness, machinability and weldability |
| Medium carbon steel | 0.3% to 0.6% | Low hardenability. Medium strength, ductility and toughness |
| High carbon steel | 0.6% to 2% | High hardness and strength. Low ductility |
Common applications for Carbon Steel
- Aerospace:In the aerospace industry, carbon steel tubes are used to manufacture aircraft structures, propulsion systems and other critical components.Construction and Building Engineering: Carbon steel pipes are used in the supports and frames of building structures such as stair handrails, railings, brackets and ductwork.
- Oil and Gas Transmission: Carbon steel pipes are used in the oil and gas industry to transport, distribute and store oil and gas. These pipelines can be used in crude oil pipelines, natural gas transmission pipelines and refinery facilities.
- Manufacturing: In manufacturing, carbon steel pipes are often used to make parts for machinery, vehicles, conveyor belts and other industrial equipment.
- Automobile manufacturing: Carbon steel pipes are used to make automobile chassis, exhaust systems and other auto parts.
- Infrastructure construction: Carbon steel pipes are used in drainage systems, bridge supports and other structures in infrastructure projects such as roads, bridges and tunnels.
What is stainless Steel?
One of the most common and best-known steels, stainless steel serves many purposes and can be used in a variety of applications. However, it is not as hard and therefore isn’t used when strength and hardness are factors.This material is made with steel combined with chromium, which helps it resist corrosion. Stainless steel is best for parts and products that will be in constant contact with water, and it will last much longer than other metals.There are numerous varieties of stainless steel, and each one has its own unique characteristics.
Types of stainless Steel
| Type of Stainless Steel | Composition | Properties |
| Austenitic Stainless Steel | 18% chromium, 8% nickel | Superior corrosion resistance, excellent formability |
| Ferritic Stainless Steel | 12%-30% chromium, under 0.20% carbon | Magnetic, good corrosion resistance, cannot be hardened by heat treatment |
| Martensitic Stainless Steel | 11.5%-18% chromium, up to 1.2% carbon, includes nickel | High strength, hardness, can be hardened by heat treatment |
| Duplex Stainless Steel | Approx. 22% chromium, 5% nickel, 3% molybdenum | Ultra high strength, improved corrosion resistance, especially against stress corrosion cracking |
| Precipitation Hardening Stainless Steel | Varies, includes elements like aluminum, copper, niobium | Can be hardened by heat treatment, high tensile strength and corrosion resistance |
Common applications for Stainless Steel
- Construction: Given its aesthetic quality and durability, stainless steel finds use in the construction industry for roofs, handrails, claddings, etc.
- Automotive: You will also see them applied in the automotive industry. Stainless steel looks good, doesn’t rust easily, and lasts a long time. That’s why it’s a good choice for car parts like exhaust systems.
- Medical: Due to their high corrosion resistance and ease of cleaning, and sterilization properties, stainless steel is suitable for medical usage. They are used to manufacture surgical instruments and other healthcare equipment.
- Food processing: Once again, its hygienic, ease of cleaning, and corrosion resistance properties come into play, making stainless steel suitable for several applications in the food industry.
What is the strength of metal?
The strength of a metal is its ability to withstand the action of external forces without breaking. Tensile strength, also called ultimate strength, is the maximum strength developed in a metal in a tension test. The tension test is a method for determining the behavior of a metal under an actual stretch loading. This test provides the elastic limit, elongation, yield point, yield strength, tensile strength, and the reduction in area. Tensile tests are normally taken at standardized room temperatures but may also be made at elevated temperatures.
Strength comparison of different types of steel
| Properties | carbon steels | Alloy Steels | Stainless steels | Tool Steels |
| Density (1000 kg/m3) | 7.85 | 7.85 | 7.75-8.1 | 7.72-8.0 |
| Elastic Modulus (GPa) | 190-210 | 190-210 | 190-210 | 190-210 |
| Poisson’s Ratio | 0.27-0.3 | 0.27-0.3 | 0.27-0.3 | 0.27-0.3 |
| Thermal Expansion (10-6/K) | 11-16.6 | 9.0-15 | 9.0-20.7 | 9.4-15.1 |
| Melting Point (°C) | 1371-1454 | |||
| Thermal Conductivity(W/m-K) | 24.3-65.2 | 26-48.6 | 11.2-36.7 | 19.9-48.3 |
| Specifc Heat (J/kg-K) | 450-2081 | 452-1499 | 420-500 | |
| Electrical Resistivity(10-9W-m) | 130-1250 | 210-1251 | 75.7-1020 | |
| Tensile Strength (MPa) | 276-1882 | 758-1882 | 515-827 | 640-2000 |
| Yield Strength (MPa) | 186-758 | 366-1793 | 207-552 | 380-440 |
| Percent Elongation (%) | 10-32 | 4-31 | 12-40 | 5-25 |
| Hardness (Brinell 3000kg) | 86-388 | 149-627 | 137-595 | 210-620 |
What are the common types of metal strength?
Tensile Strength
This is the maximum amount of pulling or stretching that a metal can withstand without being permanently damaged. It is the measure of how much tension a metal can withstand. If an external force is applied to metal and its yield point is passed, some of the resulting deformations that follow are permanent and cannot be reversed. That is the tensile strength of the metal.Tensile strength is further divided into three parts, namely:
- Yield Strength: this is the strength a metal can withstand without permanent deformation. It can also be said to be the maximum strength a component can withstand before plastic deformation. Engineers and manufacturers calculate yield strength to know the maximum load an object can accommodate.
- Breakable strength: this is the stress coordinate on the stress-strain curve at the point of failure.
- Ultimate strength: the maximum tensile, compressive, or shearing stress that a specific unit area of metal can withstand without breakage or deformation. In other words, it is the maximum amount of stress a metal can endure.
Impact Strength
This is a measure of how much impact or suddenly applied to force a metal can withstand before its failure. Impact strength is used in measuring the amount of energy the metal can absorb before it fractures, tears or damage. Therefore, if you need metal for a project and you need to know the amount of energy it can absorb, the impact strength test is what you should do.
A common misconception is that high impact strength is equivalent to a high degree of material hardness. Therefore, materials with high impact strength are hard materials. Unfortunately, this is not always true. Thus, a high impact strength does not always mean a high degree of hardness.Some of the factors that affect the impact strength of materials include temperature (increase in temperature increases impact strength), material thickness (increase in thickness reduces impact strength), and notch radius (reducing the notch radius lowers the impact strength).
Compressive Strength
Like the name sounds, compressive strength refers to the maximum amount of pressure or compression a metal can withstand without damage. To test the compressive strength of a metal, you’ll need a universal testing machine. This machine will gradually apply increased load on the metal until it begins to deform. The point at which deformation starts to occur is the compressive strength of the metal.
Why is metal strength so important?
The strength of a metal can help you determine if it is suitable for your application. Strength is crucial as it determines whether a machine part will serve its intended purpose.
Mechanical and Structural Design
When it comes to mechanical and structural elements, engineers and designers must consider the strength of the part. This strength consideration will help determine the precise point at which the metal may fail or break. Therefore, they can set limits and establish reasonable limits for specially designed parts.
material selection
Metal strength is a key property in selecting materials that can meet the needs of different industrial applications. Different metals have different strength levels. Some metals are well suited for high stress applications, while others are better suited for low stress applications.If low-strength metals are used instead of high-strength metals, the structure may be prone to deformation. For example, parts for heavy machinery require high-strength metals. Typically, steel or titanium are ideal for this job.
If you use low-strength metals in components used to lift cranes, you will only compromise the integrity of the components. This results in the product not serving its intended purpose and wasting the company’s time, energy and resources.
Durability and safety
Strength determines the durability of parts made from such metals, which is especially important for parts subjected to high stress applications. Additionally, the strength of the metal helps establish limits to avoid application failure. Knowing the strength grade of a metal improves the safety of your part design. You will ensure that these parts can adequately handle the required loads without causing harm to the user.
Processes That Enhance Metal Strength
1. Solid Solution Strengthening and alloying
This is the method used for the alloyed metals mentioned previously where it is used to improve the strength of pure metal. Solid solution strengthening involves forming a “solid solution” by adding atoms of an alloying element to the crystal lattice structure of the base metal .
2. Heat treating
This special process may be done at any point in manufacturing a metal part to enhance its properties. During the heating process, the metal’s microstructure is altered which makes a metal or alloy stronger, tougher, and more durable. Below are the common methods of heat treatment:
- Annealing- Metals like copper, silver, aluminum, steel, and brass are heated to lessen their chances of fracturing while being worked on. In annealing, there are three phenomena that happen, recovery, recrystallization, and grain growth.
- Tempering- tempering involves heating the metal to a temperature just below its hardening temperature and holding it at a specified period. This process is done to reduce the brittleness of metal while still retaining its hardness and strength.
- Normalization- This process is done to make steel tougher and ductile.
- Hardening- In this process, the metal is heated at a sufficient temperature that is high enough to dissolve solute-rich precipitates. This process then increases the metal’s hardness and strength. The downside to this however is that the metal has already lost its ductility, making it brittle.
3. Strain Hardening or cold working
This method involves strengthening metal by inducing plastic deformation to increase its hardness, yield strength, and tensile strength. The dislocations made during this process result in entanglement in the grain dislocation. This entanglement then prevents further deformation in the grains affected, hence increasing the mental strength. Strain hardening is commonly seen in cold working and forming processes such as squeezing, shearing and bending.
alloy steel vs carbon steel
Technically or by definition, carbon steel itself is also an alloy. However, due to the vast differences between alloys and carbon steel, they are not considered alloys. Carbon steel is not inherently fragile, and alloy steel simply takes the inherent strength to the next level for high-strength applications.
Alloys vs. Carbon Steel: Strength
Alloy steel is much stronger than carbon steel due to the addition of various alloying elements such as chromium and nickel. Likewise, alloy steels have higher yield and tensile strengths, making them suitable for many intensive applications where strength is required.
Alloys vs. Carbon Steel: Hardness
Elements such as tungsten and vanadium are known for their hardness and do not require any additional processing (such as heat treatment). Adding these elements to steel alloys can also increase overall hardness and resistance to wear/indentation.Carbon steel also has good hardness after tedious processes such as heat treatment and tempering, but it is still not comparable to alloy steel.
Alloy vs Carbon Steel: Durability
Generally, steel of any kind is pretty durable and that’s why it’s so commonly used across various industries. However, alloy steel possesses higher strength, hardness, and overall corrosion resistance than its carbon counterpart. Carbon steel can quickly corrode in many harsher environments and may even require multiple treatments to enhance its longevity and performance.
Alloy vs Carbon Steel: Versatility
Carbon steel has a limited number of variants as there is a limit to how much carbon can be added to the mixture. Alloy steel, however, is different. There are limitless combinations to obtain specific values depending on the application requirements. From enhancing the corrosion resistance to increasing the strength or the durability of the metal, there is an alloy steel solution to meet the specific needs.
Alloy vs Carbon Steel: Processing Requirements
Naturally, carbon steel has a smaller number of elements in the mixture. So, it’s simpler to create and process. Alloy steel, on the other hand, has a variety of constituent elements and all mixtures require different processing conditions.
Alloy vs Carbon Steel: Cost
Carbon steel has a simpler composition and doesn’t need any elaborate processing. That’s why it’s considered a more cost-effective alternative to alloy steel.
alloy steel vs carbon steel vs stainless steel which is stronger？
1.alloy steel
Alloy steel is a steel material that is based on carbon steel and improves its mechanical properties and corrosion resistance by adding one or more alloying elements (such as chromium, nickel, molybdenum, etc.). The addition of these alloying elements enables alloy steel to maintain high strength while also possessing excellent toughness and wear resistance. Therefore, alloy steel is widely used in aerospace, automobile manufacturing, shipbuilding and other fields that require high strength and wear resistance.
2.carbon steel
Carbon steel is a steel material based on iron with a certain proportion of carbon added to enhance its hardness and strength. The strength and hardness of carbon steel increase with the increase of carbon content, but too high carbon content will lead to a decrease in the toughness and weldability of the steel. Carbon steel has been widely used in construction engineering, machinery manufacturing, bridge construction and other fields because of its relatively low manufacturing cost and good mechanical properties and processability.
3.stainless steel
Stainless steel is an alloy steel with excellent corrosion resistance, and its main alloying element is chromium. When the chromium content reaches a certain proportion, a dense oxide film will form on the surface of stainless steel, thus effectively preventing the steel from being corroded. In addition, stainless steel also has good aesthetics and processability, and is widely used in the food industry, chemical equipment, building decoration and other fields. However, compared to alloy steel and carbon steel, stainless steel has lower strength and is therefore less used in applications where high-strength materials are required.
Determining which alloy steel, carbon steel or stainless steel is stronger actually depends on the specific application scenario and needs. Where high strength and wear resistance are required, alloy steel has the advantage due to its excellent mechanical properties and wear resistance; where cost-effectiveness and good mechanical properties are pursued, carbon steel is the ideal choice; and where resistance is required Where corrosion and aesthetics are concerned, stainless steel stands out with its unique properties.
Longsheng: Your Trusted Sheet Metal Fabrication Design Company
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Our team of experts has the experience to perform DfM (Design for Manufacturability) analysis to improve your design. We are not only a manufacturer, but also a partner, committed to providing full support and professional advice to our customers to ensure that the design can reduce manufacturing costs while still meeting high quality standards.
If you have a design model that needs to be manufactured, please upload it to us immediately and we will provide you with an immediate quote. Choose Longsheng, choose a quality, high technical level, cost-effective sheet metal fabrication partner, let us work together to create outstanding parts for your project to achieve greater success.
conclusion
alloy steel, carbon steel and stainless steel each have their own merits and have their unique advantages in different application scenarios. Therefore, when choosing steel, we need to weigh various factors according to specific needs and application scenarios to choose the most suitable steel. No steel is the absolute “king of strength”, only the most suitable is the best.
FAQs
Which is stronger, carbon steel or stainless steel?
Carbon steel and stainless steel each have their own characteristics and advantages, and it is impossible to simply judge which one is “stronger”.High-strength versions of stainless steel may exceed regular carbon steel in terms of strength and hardness, but high-strength versions of carbon steel perform just as well.In terms of corrosion resistance, stainless steel is significantly better than carbon steel.In terms of wear resistance, carbon steel has more advantages.In terms of magnetism, there are obvious differences between the two.In terms of price, carbon steel is usually more advantageous.The choice of which steel is stronger actually depends on the specific application scenario and needs. If a material with high strength and hardness is required, and corrosion resistance is not required, then carbon steel may be a better choice; while if good corrosion resistance and beautiful appearance are required, stainless steel is more suitable.
How to choose the right steel?
Choosing the right steel requires comprehensive consideration of multiple factors such as usage requirements, strength and toughness, corrosion resistance, processing performance, cost-effectiveness, environmental requirements, appearance quality, manufacturer credibility, quality testing, quantity and transportation. By taking these factors into consideration, you can choose the steel that best suits your needs.
What is the difference between metal strength and hardness?
Strength refers to the metal’s ability to withstand an external load without deformation. On the other hand, hardness is the ability of a metal to resist scratching or penetration. Knowing metal strength will help you set limits on the maximum allowable load on components. This will help avoid damage to machinery and structures.On the other hand, hardness indicates the resistance of the metal to mechanical wear. Manufacturers prefer harder metals for parts required to withstand high stress.
Which one is stronger alloy steel or carbon steel?
The tensile strength of low-carbon steel is approximately 450 MPa and the tensile strength of high-carbon steel is 965 MPa. The alloy steel has higher tensile strength as compared to carbon steel. The tensile strength of alloy steel ranges between 758 – 1882 MPa.
resource
Boronization and Carburization of Superplastic Stainless Steel and Titanium-Based Alloys
