Difference Between 304 vs 316 Stainless Steel (SS304 vs SS316)
The main difference between 304 vs 316 stainless steel is that 304 does not contain molybdenum, while 316 contains 2-3% molybdenum and less chromium and more nickel. The addition of molybdenum provides pitting resistance in phosphoric acid, acetic acid and dilute chloride solutions and provides corrosion resistance in sulfurous acid. AISI 304 has a 18% Cr and 8% Ni and therefore known as 18/8 stainless steel, while AISI 316 stainless steel has a 16% Chromium and 10% Nickel.
SS304 vs SS316 Difference in Chemical Composition
The following table shows the chemical composition difference between 304 and 316 stainless steel (SS304 vs SS316).
|304 vs 316 Composition (%)|
|Stainless Steel||C, ≤||Si ≤||Mn ≤||P ≤||S ≤||Cr||Ni||Mo|
Difference in Mechanical Properties
Stainless 304 vs 316 mechanical properties
|SS304 vs SS316 Mechanical Properties|
|ASTM||AISI||Tensile Strength, MPa (ksi), ≥||0.2% Yield Strength, MPa (ksi), ≥||Elongation in 50 mm, %, ≥||Reduction in area, %, ≥||Brinell Hardness (HBW) ≤||Rockwell Hardness (HRBW) ≤||Condition|
|ASTM A276/A276M||304||515 (75)||205 (30)||40||50||–||–||Annealed, Hot finished|
|304||620 (90)||310 (45)||30||40||–||–||Annealed, Cold finished, ≤ 0.5 in. (12.7 mm)|
|ASTM A240/A240M||304||515 (75)||205 (30)||40||–||201||92|
Stainless 304 vs 316 Cost
AISI 304 vs 316 stainless steel cost: Taking steel plates as an example, the cost of 316 is about 1.5 times the cost of 304. The price of stainless steel depends on the price of the alloying element and the amount of the alloy (eg Ni, Cr and Mo). The price of molybdenum (Mo) is about twice that of nickel (Ni), six times that of chromium (Cr), 316 nickel content is higher than 304, and 316 contains molybdenum, while 304 does not contain it, so the cost of 316 is higher than 304.
304 vs 316 in Corrosion
Since 316 contains 2-3% molybdenum, and molybdenum can improve the pitting resistance, therefore 316 is more resistant to corrosion than 304.