Type 316 SS is more corrosion resistant than 304 SS because of its higher nickel content and the addition of molybdenum (2-3%) as an alloying element.
What Is 304 Stainless Steel?
SS304/UNS S30400/1.4301 stainless steel or 304 SS is austenitic grade steel that contains 18% chromium and 8% nickel (hence the name 18/8) and other alloying elements such as carbon, phosphorus, sulfur, silicon, and manganese. It has good corrosion resistance properties and is considered the most versatile and common stainless-steel grade in sheet metal fabrication.
304 Stainless Steel Properties
304 SS plate has unique properties making it suitable for different industries. Below are the important physical and mechanical properties of the material flat rolled product (plate, sheet, and coil):
- Melting Point 1450℃
- Density: 8.00 g/cm^3
- Thermal Expansion: 17.2 x10^-6/K
- Modulus of Elasticity: 193 GPa
- Thermal Conductivity: 16.2 W/m.K
- Tensile Strength: 500-700 Mpa
- Elongation A50 mm: 45 Min %
- Stainless Steel Hardness (Brinell): 215 Max HB
What Is 316 Stainless Steel?
SS316/UNS S31600/1.4401/1.4436 stainless steel or 316 SS is the second most popular austenitic grade of stainless steel, and it comprises iron, 10-14% nickel, and 16-18% chromium. The real distinction in the stainless steel 316 vs 304 SS comparison is the presence of molybdenum (2-3%) alongside the other alloying elements such as carbon, manganese, and silicon.
316 Stainless Steel Properties
Physical properties
- Density: 8.00 g/cm3
- Melting Point: 1400°C
- Modulus of Elasticity: 193 GPa
- Electrical Resistivity: 0.74 x 10-6 Ω.m
- Thermal Conductivity: 16.3 W/m.K
- Thermal Expansion: 15.9 x 10-6/K
Mechanical properties
The mechanical properties depend on the type of 316 stainless steel. There are three categories: 316 Bar and Section (up to 160 mm thick), stainless steel 316 Sheet (up to 8 mm thick), and ss 316 Plate (8 – 75 mm thick). Below are the mechanical properties for each category, respectively.
- Tensile strength (Mpa): 500-700, 530-680, 520-670
- Proof Stress (MPa): 200, 240, 220
- Elongation A50 mm: 4 0 Min %, 40 Min %, 45 Min %
- Stainless Steel Hardness Brinell: 215 Max HB
What is difference: Ss304 Vs Ss316
1. Composition:
SS304/UNS S30400/1.4301: Contains approximately 18% chromium and 8% nickel, along with small amounts of carbon, manganese, and silicon.
SS316/UNS S31600/1.4401/1.4436: Contains approximately 16-18% chromium, 10-14% nickel, and 2-3% molybdenum, along with small amounts of carbon, manganese, and silicon.
2. Corrosion Resistance:
Stainless steel 304: Offers good resistance to corrosion in mild environments, such as atmospheric conditions and freshwater.
Stainless steel 316: Provides superior corrosion resistance, especially in harsher environments with exposure to chloride solutions, acids, and marine environments, thanks to the addition of molybdenum.
3. Strength and Durability:
S30400: Exhibits good strength and durability suitable for a wide range of applications, including food processing equipment, architectural components, and kitchen appliances.
S31600: Offers higher tensile strength and better creep resistance than SS304, making it ideal for use in more demanding applications such as chemical processing, pharmaceuticals, marine equipment, and medical devices.
4. Temperature Resistance:
SS304: Performs well at temperatures up to 870°C (1,598°F), making it suitable for high-temperature applications such as industrial furnaces and heat exchangers.
SS316: Withstands higher temperatures than SS304, up to 925°C (1,697°F), making it preferred for applications involving extreme heat or thermal cycling.
5. Cost: Ss304 Vs Ss316 Price Difference
SS304: Generally less expensive than SS316 due to its lower nickel content.
SS316: Typically more costly than SS304 due to the addition of molybdenum and higher nickel content.
Depending on the market conditions, and several other components of the economy, the price of the SS 304 material tends to remain approximately within the range of ₹180 to ₹200. Whereas, the prices of the SS 316 material and products, depending on dimensions, finishes, etc. can vary within the range of ₹ 210 to ₹ 290. On average, the price of 316 stainless steel 40% higher than the price of 304 SS.
6. Applications:
SS304: Commonly used in various industries, including food and beverage processing, dairy equipment, architectural structures, and automotive components.
SS316: Preferred for applications requiring superior corrosion resistance, such as chemical processing, pharmaceutical manufacturing, marine environments, and medical implants.
