P355Q steel Vs P355QH steel

What are the differences between P355Q steel and P355QH steel? Do you know the grade P355QH steel? Below is the comparison of P355Q steel and P355QH steel for your reference.
P355Q steel chemical composition(％)

C

Si

Mn

P

S

N

B

Cr

Cu

Mo

Nb

Ni

Ti

V

≤0.16

≤0.4

≤1.5

≤0.025

≤0.01

≤0.015

≤0.005

≤0.3

≤0.3

≤0.25

≤0.05

≤0.5

≤0.03

≤0.06

Note: Nb+Ti+V≤0.05; Cr+Cu+Mo≤0.5
P355QH steel chemical composition(％)

C

Si

Mn

P

S

Ni

Cr

Mo

Cu

Nb

V

Ti

N

Zr

B

≤0.16

≤0.4

≤1.5

≤0.025

≤0.015

≤0.5

≤0.3

≤0.25

≤0.3

≤0.05

≤0.06

≤0.03

≤0.015

≤0.05

≤0.005

 
P355Q plate mechanical properties

Grade	Thickness mm	Yield strength(MPa)	Tensile strength (MPa)	Elongation A(％)
P355Q	≤50	≥355	490-630	≥22
	50-100	≥335	450-590
	100-150	≥315	450-590

P355QH plate mechanical properties

Grade	Delivery state	Thickness mm	Mechanical properties
P355QH	quenching and tempering	<5	ReH(MPa)	≥355
			Rm(MPa)	490～630
			A(%)	≥22
P355QH		5~50	ReH(MPa)	≥355
			Rm(MPa)	490～630
			A(%)	≥22
			Impact temperature ℃	-20
			Akv(J)	≥27
P355QH		>50~100	ReH(MPa)	≥335
			Rm(MPa)	490～630
			A(%)	≥22
			Impact temperature ℃	-20
			Akv(J)	≥27
P355QH		>100~150	ReH(MPa)	≥315
			Rm(MPa)	450～590
			A(%)	≥22
			Impact temperature ℃	-20
			Akv(J)	≥27

Both P355Q and P355QH steel are European standard boiler steel plates EN 10028-6, which are tempered and weldable fine-grained steel. P355Q boiler plate and P355QH steel plates are steel for pressure equipment, which has excellent plasticity, resistance, cold bending function and welding function.