Stainless 304

The hardness of stainless steel grades 303, 304, 305, and 316 varies based on their specific composition and heat treatment condition. Here’s a comparison of their typical hardness values in Brinell Hardness (HB) and Rockwell Hardness (HRB):

 

Hardness Comparison

 

Stainless Steel Grade Brinell Hardness (HB)	Rockwell	Hardness (HRB)
303 (Annealed)	200 HB	95 HRB
304 (Annealed)	201 HB	92 HRB
305 (Annealed)	183 HB	89 HRB
316 (Annealed)	217 HB	95 HRB

Stainless Steel Grade

Rockwell Hardness (HRB)

303 (Annealed)

200 HB

Brinell Hardness (HB)

95 HRB

304 (Annealed)

201 HB

92 HRB

305 (Annealed)

183 HB

89 HRB

316 (Annealed)

217 HB

95 HRB

Stainless Steel Grade

Brinell Hardness (HB)

Rockwell Hardness (HRB)

303 (Annealed)

200 HB

95 HRB

304 (Annealed)

201 HB

92 HRB

305 (Annealed)

183 HB

89 HRB

316 (Annealed)

217 HB

95 HRB

Key Points:

 

   •      303 has slightly lower hardness than 304 but is easier to machine.

   •      304 is slightly harder than 303 and is commonly used in general applications.

   •      305 has the lowest hardness due to its higher nickel content, making it ideal for deep drawing.

   •      316 is the hardest among them due to its molybdenum content, which also improves corrosion resistance.

 

If cold-worked, these values increase significantly, especially for 304 and 316, which can achieve much higher hardness through work-hardening.