Home ProductsSteel Round Bar

SAE4340 Steel Round Bar Hot Rolled Annealed 228HB Surface Peeled

Certification
China JIANGSU MITTEL STEEL INDUSTRIAL LIMITED certification
China JIANGSU MITTEL STEEL INDUSTRIAL LIMITED certification
Customer Reviews
this is the second order l buy this company ,quality is very good ,same as europure quality .we will go on ccooperate with this company .

—— Andrew Greg - Turkey

200 ton Stainless steel sheet is arrived on 10th Oct 2014 , the quality is very good.,deliver time is very fast It's very lucky we find this factory

—— Mechile Kilar Chard - Brazial

We Have Cooperate With this Factory Many Years , Everything Goes Very Well.l Like This Factory !

—— Tony Hilton - Poland

This is Our Thrid Time Buy from Mittel,Quality is Very Goods ,We Are Glad to Find This Reliable Factory

—— Natalya Ugay-Russia

Quality is very good and delivery time very fast ,we want to do long terms business with this company

—— Pongpol Pluemsati-Thailand

I'm Online Chat Now

SAE4340 Steel Round Bar Hot Rolled Annealed 228HB Surface Peeled

SAE4340 Steel Round Bar Hot Rolled Annealed 228HB Surface Peeled
SAE4340 Steel Round Bar Hot Rolled Annealed 228HB Surface Peeled SAE4340 Steel Round Bar Hot Rolled Annealed 228HB Surface Peeled SAE4340 Steel Round Bar Hot Rolled Annealed 228HB Surface Peeled

Large Image :  SAE4340 Steel Round Bar Hot Rolled Annealed 228HB Surface Peeled

Product Details:
Place of Origin: China
Brand Name: Mittel
Certification: SGS ISO MTC
Model Number: AISI 4340
Payment & Shipping Terms:
Minimum Order Quantity: 100KGS
Price: 1.65USD/KG
Packaging Details: Wooden Pallet BOX
Delivery Time: 7 Working Days
Payment Terms: L/C, T/T
Supply Ability: 80000KGS

SAE4340 Steel Round Bar Hot Rolled Annealed 228HB Surface Peeled

Description
Steel Grade: 4340 Alloy Or Not: Is Alloy
Technique: Hot Rolled Application: Structural Steel Bar,Die Steel Bar,Tool Steel Bar,chemical,shipbuilding
Type: Alloy Steel Bar Standard: ASTM,DIN,AISI,JIS
Special Use: Mold Steel Shape: Round
Length: 1--12m Surface: Black Or Bright
High Light:

Surface Peeled Round Bar Hot Rolled

,

228HB Steel Round Bar

,

Annealed Round Bar

AISI / SAE 4340 ALLOY STEEL

CHEMICAL ANALYSIS
C% Carbon 0.38 – 0.43
Mn% Manganese 0.6 – 0.8 max
P% Phosphorus 0.035 max
S% Sulfur 0.040 max
Si% Silicon 0.15 – 0.3
Ni% Nickel 1.65 – 2.0
Cr% Chromium 0.7 – 0.9
Mo% Molybdenum 0.2 – 0.3

GENERAL CHARACTERISTICS OF ALLOY STEEL 4340

4340 is a nickel-chromium-molybdenum alloy steel known for its toughness and its ability to attain high strengths in the heat-treated condition. It has very good fatigue resistance.

This alloy, 4340, may be heat treated to high strength levels while maintaining good toughness, wear resistance and fatigue strength levels, combined with good atmospheric corrosion resistance, and strength.

APPLICATIONS

Commercial and military aircraft, automotive systems, forged hydraulic and other machine tool applications, forged steel crankshafts.

FORGING

Forging should be carried out between 2250 and 1800 º F (1230 and 980 º C.). Parts should be slow cooled after forging in ashes or sand etc.

HEAT TREATMENT

Heat treatment after forging is carried out to render the steel suitable for machining, and to meet the mechanical property limits specified for the steel’s particular applications. There are several ways to heat treat a given steel part and it is only through practice that the optimum temperature and conditions may be defined. The following information should be taken as a guide only.

ANNEALING

To obtain a pearlitic structure on certain parts for machining, 4340 should be annealed at a nominal temperature of 1525 º F (830 º C,) cooling to 1350 º F (730 º C) and furnace cooling to 1130 º F (610 º C) at a rate of 20 º F (11 º C) per hour, then air cooling. This process, known as full annealing, is very time consuming as it involves slow cooling over the entire temperature range from the austenitizing temperature to a temperature well below that at which transformation is complete.

To obtain a spheroidized structure in 4340 grade involves austenitizing at 1380 º F (750 º C,) furnace cooling to 1300 º F (705 º C) then to 1050 º F (565 º C) at a rate of 5 º F (3 º C) per hour. This structure will probably result in better machinability than will the coarse lamellar pearlite structure obtained by the full anneal process.

NORMALIZING

This process is defined as heating a steel to a temperature above the ferrite to austenite transformation temperature, then cooling in air to a temperature well below this transformation temperature. The treatment may be carried out on forged products as a conditioning treatment prior to final heat treatment. Normalizing also serves to refine the structure of forgings that might have cooled non-uniformly from their forging operation. The nominal normalizing temperature for 4340 grade is 1500 º F (815 º C,) but production experience may necessitate a temperature either 50 º F (10 º C) above or below this temperature. . As a rule of thumb, when forgings are normalized before, say, carburizing or hardening and tempering, the upper range of normalizing temperatures is used. When normalizing is the final heat treatment, the lower temperature range is used.

HARDENING

This heat treatment results in the formation of martensite after quenching, resulting in increased hardness and tensile strength. A temperature range of 1500 – 1550 º F (815 – 845 º C) is the normal austenitizing temperature for direct hardening of 4340 grade. Oil quenching is normally used for 4340 as the alloy’s hardenability is suited to this quenching method.

TEMPERING

Tempering is carried out to relieve stresses from the hardening process, but primarily to obtain mechanical properties required for the final application. The actual tempering temperature will be chosen to meet the required properties, and in many cases will be a matter of trial and error.

This grade 4340 may also be hardened by nitriding or flame or induction hardening.

MACHINABILITY

This grade is readily machinable, with either a coarse lamellar pearlitic structure or a spheroidized structure being best advised, depending upon section size and complexity and amount of machining to be carried out. If there is doubt about the suitability of any other structure, then a spheroidizrd structure should be aimed for in heat treatment.

WELDING

This grade is readily welded in the annealed condition, but welding in the hardened and tempered condition should be avoided where possible because of the effect on mechanical properties. Welding in the nitrided or flame or induction hardened conditions is not recommended.

 

SAE4340 Steel Round Bar Hot Rolled Annealed 228HB Surface Peeled 0SAE4340 Steel Round Bar Hot Rolled Annealed 228HB Surface Peeled 1SAE4340 Steel Round Bar Hot Rolled Annealed 228HB Surface Peeled 2

Contact Details
JIANGSU MITTEL STEEL INDUSTRIAL LIMITED

Contact Person: Gao Ben

Tel: +8618068357371

Send your inquiry directly to us (0 / 3000)