THE DESCRIPTIONS OF EN 42CRMO4 STEEL |AISI 4140

 42CrMo4 is a heat treatable steel which contains at least 0.9%Cr,0.15%Mo as strengthening elements.After quenched and tempered, It obtains high strength, good low-temperature impact toughness with a typical tensile strength of 900 -1200 N/mm2. 42CrMo4 steel has better performance than 34CrMo4 steel due to the higher carbon and chromium content.Similar to AISI 4140,only a little difference in Mn,Cr content.This material also has good machinability,good wear-resistance,but the temper brittleness is not obvious,and poor in weldability.

2.Chemical Composition

Grade	C	Si	Mn	Cr	Mo	P	S
42CrMo4/1.7225	0.38-0.45	≤ 0.4	0.6-0.9	0.9-1.2	0.15-0.3	≤ 0.025	≤ 0.035
42CrMoS4/1.7227	0.38-0.45	≤ 0.4	0.6-0.9	0.9-1.2	0.15-0.3	≤ 0.025	0.02-0.04

3.Relevant Standards

USA	UK	China	Japan	France	Russia
4140	EN19/708M40	42CrMo	SCM440	42CD4	42HM

4. Mechanical Property

Diameter d mm	≤ 16	16-40	40-100	100-160	160-250
Thickness t mm	< 8	8-20	20-60	60-100	100-160
Yield Strength Mpa	≥900	≥750	≥650	≥550	≥500
Tensile Strength Mpa	1100-1300	1000-1200	900-1100	800-950	750-900
Elongation, %	≥10	≥11	≥12	≥13	≥14
Reduction of area ,%	≥40	≥45	≥50	≥50	≥55
impact	≥30	≥35	≥35	≥35	≥35

5.Forging

42CrMo4 forging temperature:900 – 1100°C ,cooling as slowly as possible in still air or in sand after forged.

6.Heat Treatment

• Normalizing:  850 – 880°C,Cooling in air
• Soft Annealing:680 – 720°C,Cooling in furnace
• Stress relieve:450-650°C,Cooling in air
• Hardening:820 – 880°C,oil or water quench
• Tempering:540 – 680°C,Cooling in air

7.Surface Hardness

• Treated to improve shearability (+S):Max 255HB
• Soft annealed (+A):Max 241HB
• Pre Quenched and tempered:280-320HB
• Flame or induction hardening:Min 53HRC

NORMAL HARDENABILITY +H (850°C - hardness HRC – distance mm)
Distance mm	1.5	3	5	7	9	11	13	15	20	25	30	35	40	45	50
HRC Min	53	53	52	51	49	43	40	37	34	32	31	30	30	29	29
HRC Max	61	61	61	60	60	59	59	58	56	53	51	48	47	46	45

8.Application

42CrMo4 has high strength and wear-resistance,widely used in many industries.

Components with high strength and toughness for tools, automotive parts,mechanical engineering, armament components,such as geer wheels,pinions,connecting rods,parts for mechanical engineering.

Datong Hydraulic is a professional manufacturer of 42Crmo4 steel products, such as hydraulic cylinder parts 42Crmo4 cylinder barrel, 42Crmo4 chrome rod, 42Crmo4 hollow bar ,

 If you are interested in our hard chrome piston rod, chrome rod, chrome plated bars,welcome to contact us online or email to andy@datong-hydraulic.com.