Is 2205 stainless better than 316?

 

Composition

Table 1 provides the compositional ranges for grade 2205 duplex stainless steel.

Table 1 - Composition ranges for 2205 grade stainless steels

Grade		C	Mn	Si	P	S	Cr	Mo	Ni	N
2205 (S31803)	Min Max	- 0.030	- 2.00	- 1.00	- 0.030	- 0.020	21.0 23.0	2.5 3.5	4.5 6.5	0.08 0.20
2205 (S32205)	Min Max	- 0.030	- 2.00	- 1.00	- 0.030	- 0.020	22.0 23.0	3.0 3.5	4.5 6.5	0.14 0.20

Mechanical Properties

The typical mechanical properties of grade 2205 stainless steels are listed in the table below. Grade S31803 has similar mechanical properties to that of S32205.

Table 2 - Mechanical properties of 2205 grade stainless steels

Grade	Tensile Str (MPa) min	Yield Strength 0.2% Proof (MPa) min	Elongation (% in 50mm) min	Hardness
				Rockwell C (HR C)	Brinell (HB)
2205	621	448	25	31 max	293 max

Physical Properties

The physical properties of grade 2205 stainless steels are tabulated below. Grade S31803 has similar physical properties to that of S32205.

Table 3 – Physical properties of 2205 grade stainless steels

Grade	Density (kg/m3)	Elastic Modulus (GPa)	Mean Co-eff of Thermal Expansion (μm/m/°C)			Thermal Conductivity (W/m.K)		Specific Heat 0-100°C ( J/kg.K)	Electrical Resistivity (nΩ.m)
			0-100°C	0-315°C	0-538°C	at 100°C	at 500°C
2205	7800	190	13.7	14.2	-	19	-	418	850