GB 3077 50B steel

Material: 50B
Standard: alloy structural steel

GB 3077 50B grade steel is a kind of alloy structural steel. This steel has higher hardness, strength, wear resistance and hardenability than 45# steel. The critical hardenable diameter in water is 17~30mm, and the critical hardenable diameter in oil is 7~15mm.

GB 3077 50B Chemical Composition

Grade	Chemical Composition
50B	The Element (%)
	C	Si	Mn	Cr	Mo	Ni	W	B	Al	Ti	V
	0.47-0.55	0.17-0.37	0.60-0.90	-	0.40-0.50	-	-	0.0005-0.0035	-	-	-

GB 3077 50B Mechanical Property     

Grade	Mechanical Property
50B	Yield Strength Mpa	Tensile Strength Mpa	Elongation %	Impact energy J
	785	540	10	39

GB 3077 50B steel application

GB 3077 50B steel is usually used in quenched and tempered condition to make parts that are slightly larger and more expensive than 45# steel; such as the crank handle of tractors and other similar parts. In addition, 40cr steel can be replaced when manufacturing small-sized, less demanding parts.