Views: 107 Author: Good Du Publish Time: 2023-03-27 Origin: Site
Stainless steel is a kind of steel. Steel refers to steel which contains less than 2% carbon (C) and more than 2% iron. Alloy elements such as chromium (Cr), nickel (Ni), manganese (Mn), silicon (Si), titanium (Ti), molybdenum (Mo) are added to the steel during the smelting process to improve the performance of the steel and to make the steel corrosion resistant (i.e. not rusty), which is commonly referred to as stainless steel.
304 and 316 stainless steels are austenitic stainless steels. They are common materials in the field of industrial piping.
What are the Differences between 304 and 316 Stainless Steels ?
1. Different Chemical Composition
Type | C max | Mn max | P max | C max | Si max | Cr | Ni | Mo |
304 | 0.08 | 2.0 | 0.045 | 0.03 | 1.0 | 18-20 | 8-12 | |
316 | 0.08 | 2.0 | 0.045 | 0.03 | 1.0 | 16-18 | 10-14 | 2-3 |
The composition of 304 stainless steel is composed of 18% chromium and about 8% nickel. In addition to chromium and nickel, 316 stainless steel also has about 2% molybdenum. Different components also make a difference in performance. 316 increases the proportion of Ni content, so its corrosion resistance is better than 304, and it is more suitable for use in chemical industry, seawater and other environments. 316 stainless steel has excellent corrosion resistance, atmospheric corrosion resistance and high temperature strength due to molybdenum addition.
2. Different Performance
Type | UTS N/mm | Yield N/mm | Elongation % | Hardness HRB | Comparable DIN number | |
wrought | cast | |||||
304 | 600 | 210 | 60 | 80 | 1.4301 | 1.4308 |
316 | 560 | 210 | 60 | 78 | 1.4401 | 1.4408 |
3. Different Applications
304 stainless steel and 316 stainless steel are both food-grade materials, but 316 is more used in some fields such as medical devices because of its better corrosion resistance and acid and alkaline resistance. 304 stainless steel is more used in our kitchens, such as tableware, kitchenware, stainless steel countertops, etc.
4. Different Prices
316 stainless steel is more superior in performance and therefore more expensive than 304 stainless steel.
Why is Stainless Steel Rusty ?
Stainless steel can also rust under certain conditions. Stainless steel has the ability to resist atmospheric oxidation, but also to corrode in media containing acids, bases and salts - i.e. corrosion resistance. However, its corrosion resistance varies with the chemical composition of the steel itself, the state of protection, the service conditions and the type of environmental media. For example, 304 steel pipe has absolutely excellent rust resistance in a dry and clean atmosphere, but it will soon rust in a salt-laden sea fog when moved to the seaside area; 316 steel pipe performs well. Therefore, it is not any stainless steel and can be corrosion-resistant and rust-free in any environment.
Stainless Steel Gredes in ASTM A403
Common Names | |||
Grade WpA | Grade CRA | UNS Designation | Type |
WPXM-19 | CRXM-19 | S20910 | XM-19C |
WP304 | CR304 | S30400 | 304 |
WP304L | CR304L | S30403 | 304L |
WP304H | CR304H | S30409 | 304H |
WP304N | CR304N | S30451 | 304N |
WP304LN | CR304LN | S30453 | 304LN |
WP309 | CR309 | S30900 | 309 |
WP310S | CR310S | S31008 | 310S |
WPS31254 | CRS31254 | S31254 | ... |
WP316 | CR316 | S31600 | 316 |
WP316L | CR316L | S31603 | 316L |
WP316H | CR316H | S31609 | 316H |
WP316N | CR316N | S31651 | 316N |
WP316LN | CR316LN | S31653 | 316LN |
WP317 | CR317 | S31700 | 317 |
WP317L | CR317L | S31703 | 317L |
WPS31725 | CRS31725 | S31725 | 317LMC |
WPS31726 | CRS31726 | S31726 | 317LMNC |
WP321 | CR321 | S32100 | 321 |
WP321H | CR321H | S32109 | 321H |
WPS33228 | CRS33228 | S33228 | ... |
WPS34565 | CRS34565 | S34565 | ... |
WP347 | CR347 | S34700 | 347 |
WP347H | CR347H | S34709 | 347H |
WP348 | CR348 | S34800 | 348 |
WP348H | CR348H | S34809 | 348H |
We(Shanghai Zhucheng Pipe Fittings Manufacturing Co Ltd) is professional engaged in manufacture of Steel pipe(seamless/welded), pipe fittings(butt welding, socket weld, threaded) and flanges in pipe system of all kinds of materials(carbon steel, stainless steel, alloy steel, low temp steel, pipeline steel). In order to get to a successful cooperation with customers, normally we are willing to provide free samples to all customers if required. (The customer should be responsible for the freight and the samples should be in common size and materials)