The 301 and 304 stainless steel alloys play a significant role in the industry. Both of these alloys belong to the austenitic stainless steel family. Both grades have excellent strength and corrosion resistance properties. The 301 and 304 stainless steel grades have many similarities and also some differences in their chemical composition and physical properties.
You can easily choose between 301 and 304 stainless steel alloys according to your final product. It depends upon the environment where you use the product. The 301 grade is frequently a superior choice due to its tensile strength if you are producing a product that won’t be exposed to very corrosive conditions, such as seawater or high temperatures.
The 304 grade will perform better and be more affordable in the long run if your finished product must withstand challenging conditions. Grade 301 stainless steel has 16% to 18%chromium and 6% to 8% nickel contents in its composition.
On the other hand, grade 304 has 18% to 20 % chromium and 8% to 10% nickel in composition. Grades 301 and 304 have some differences in their composition; therefore, they have different properties and are used in different applications.
If you want to choose one of these grades for making your desired product, this article is very helpful for you.
This guide will discuss the five main differences between grades 301 and 304 stainless steel.
What is grade 301 stainless steel?
Grade 301 is a chromium nickel-based austenitic stainless steel alloy. The strength and ductility of 301 stainless steel alloy can be increased by cold working. Heat treatment cannot harden it. Type 301 is not magnetic when annealed but grows more magnetic as it is cold-worked. When cold-wrought, this chromium-nickel stainless steel alloy has great strength and ductility.
The grade 301 stainless steel is also known as UNS S30100. This type of stainless steel mostly supplies in the form of wires and strips. Corrosion resistance in type 301 steel is comparable to that in type 302.
The type 301 material reaches its highest level of corrosion resistance in the cold worked and annealed condition. In the tempered condition, it is preferred over types 302 and 304 because the larger elongations make production easier.
What is grade 304 stainless steel?
The austenitic grade of stainless steel 304 can be significantly deep drawn. Due to this characteristic, 304 is the most common grade utilized in products like saucepans and sinks. The most adaptable and popular type of stainless steel is 304. Even now, type 304 is generally referred to by the old term 18/8, which comes from the nominal composition of 18% chromium and 8% nickel.
Grade 304 stainless steel is known for its excellent toughness at low temperatures. Grade 304 stainless steel is easy to clean, simple to fabricate, and has a lovely appearance. It also offers low-temperature qualities that respond well to hardening by cold working.
Better corrosion resistance is found in Grade 304 stainless steel than in Type 302. Grade 304 has excellent drawing, forming, and high ductility. When cold worked, something that is essentially non-magnetic turns slightly magnetic. Low carbon concentration results in less intergranular corrosion and less carbide precipitation in the heat-affected zone during welding.
Summary of the difference between 301 and 304
Both these 301 and 304 stainless steel alloys are mostly used in industries due to their excellent properties. Grades 301 and 304 have many similarities and some differences in their composition and properties.
Now discuss some differences between 301 and 304 stainless steel alloys.
Chemical properties
The chemical composition of grade 301 stainless steel is listed below.
| Elements | Max | Min |
| Carbon | 0.15% | 0.15% |
| Manganese | 2.0% | 2.0% |
| Silicon | 1.0% | 1.0% |
| Chromium | 16.00% | 18.00% |
| Nickel | 6.00% | 8.00% |
| Aluminum | 0.75% | 0.75% |
| Phosphorus | 0.040% | 0.040% |
| Sulfur | 0.030% | 0.030% |
| Copper | 0.75% | 0.75% |
| Nitrogen | 0.10% | 0.10% |
| Iron | Balance | Balance |
For the Chemical composition of grade 304 stainless steel see the given table
| Elements | Max | Min |
| Carbon | 0.08% | 0.08% |
| Manganese | 2.0% | 2.0% |
| Silicon | 0.75% | 0.75% |
| Chromium | 18.00% | 20.00% |
| Nickel | 8.00% | 12.00% |
| Phosphorus | 0.045% | 0.045% |
| Sulfur | 0.030% | 0.030% |
| Nitrogen | 0.10% | 0.10% |
| Iron | Balance | Balance |
Mechanical properties
Mechanical properties of grade 301 stainless steel at room temperature in annealed condition
| Tensile strength | Yield strength | Elongation | Hardness |
| 515 MPa Min | 205 MPa Min | 40% Min | 150-200 HV |
Mechanical properties of grade 304 stainless steel at room temperature in annealed condition
| Tensile strength | Yield strength | Elongation | Hardness |
| 480 MPa Min | 205 MPa Min | 40% Min | 150-200 HV |
Physical properties
Physical properties of grade 301 stainless steel
| Density | Melting range | Modulus of Elasticity |
| 7.88g/cm3 | 1399-1421 °C | 193 GPa |
Physical properties of grade 304 stainless steel
| Density | Melting range | Modulus of Elasticity |
| 8.03 g/cm³ | 1400-1450 °C | 260 GPA |
Corrosion resistance
Good qualities for resisting corrosion can be found in stainless steel grade 301. This grade shows good corrosion resistance when exposed to mildly corrosive surroundings at room temperature.
When exposed to various conditions and corrosive media, stainless steel 304 shows high corrosion resistance. In situations with chlorides, pitting, and crevices corrosion 304stainless steel shows excellent corrosion resistance. At temperatures above 60 °C, stress corrosion cracking might take place.
Cost
Some elements have the same percentage in the composition of these 301 and 304 stainless steel alloys. But compared to grade 301, grade 304 stainless steel has more chromium and nickel contents. Due to extra chromium and nickel contents, grade 304stainless steel is generally more costly than grade 301.
Fabrication of 301 and 304 grades of stainless steel
For the fabrication of grade 301 and 304 stainless steel, we used many processes like bending, rolling, punching, welding, hot and cold rolling, cutting, and finishing. Grade 301 and 304 most commonly used products are wire, strips, tubes, pipes, plates, and coils. For the fabrication of 301 and 304, we use specific tools.
Before use, tools and work surfaces must be properly cleaned. These safety measures are required to prevent easily corroded metals from infecting 301 and 304 stainless steel in a way that could discolor the finished product.
Applications of 301 and 304 stainless steel alloys
Applications of 301 stainless steel:
Grade 301 stainless is used in many applications due to its excellent corrosion resistance and high strength. Some useful applications of grade 301 stainless steel are given below.
- Making structural elements for rail cars
- Airframe pieces
- Roadway trailer parts
- Vehicle wheel covers
- Clips and holders for wiper blades
- Clips for stove elements
- Frames of the screens
- Springs of the toasters
- Draped walls
- Structural parts of aircraft
- Utensils, trailer bodies, conveyor belts, rim roof drainage devices, and architectural and automotive items.
Applications of grade 304 stainless steel:
The grade 304 stainless steel has outstanding corrosion resistance and durability. Due to these properties, grade 304 stainless steel is very popular among stainless steel alloys. Grade 304 stainless steel alloy is mostly used in
- Saucepans
- Flatware and cutlery
- Paneling for buildings
- Tubing
- Brewing, dairy, food, and pharmaceutical manufacturing machinery
- Bolts, screws, nuts, and springs.
Additionally, stainless steel grade 304 is utilized in milk trucks, railroad cars, pipelines, valves, homogenizers, sterilizers, and storage and hauling tanks.
It is widely used in the brewing sector in storage and railroad wagons, pipelines, yeast pans, and fermentation vats.
Type 304 is also used for all handling, crushing, preparation, storage, and transporting equipment in the citrus and fruit juice industries.
Which one is better, 301 or 304?
Due to their outstanding properties, the demand for 301 and 304 stainless steel alloys is increasing daily. When you ask this question about which grade is the best between 301 and 304, the answer to this question depends upon your desired product.
Grade 301 stainless steel is most likely the best option for applications where the material of your product won’t be exposed to high temperatures, seawater, or other high-corrosion conditions, and you require a higher tensile strength.
However, grade 304 stainless steel will typically be the superior choice for usable life and long-term cost-effectiveness in areas that need to support a load through high temperatures or be subjected to extremely corrosive environments. The durability of grade 304 stainless is better than grade 301 due to more chromium contents.
The cost of grade 304 stainless steel is relatively higher than 301 stainless steel, but the product’s usability is long-lasting. The products made with grade 304 stainless steel have very few maintenance issues. Grade 301 is still valuable material, even this. In cases when the project’s cost is a top priority, grade 301 is an obvious choice. Many interior locations can accommodate its applications.
Conclusion
The 301 and 304 stainless steel alloys have outstanding corrosion resistance, strength, and durability. Now you can easily choose one of them according to your product. If your product is used for indoor purposes, grade 301 stainless steel is best for you.
On the other hand, 304 is the perfect material for you if your equipment and components are exposed to high temperatures or harsh corrosive conditions.
