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{"title":"ASTM A29\/A29m Hot Rolled Alloy Steel Round Bars SAE4340 10-350mm","imgUrl":"https:\/\/img.chinax.com\/nimg\/bb\/a1\/eb9afbd48509c13f9c6fa7b71d79-200x200-1\/astm_a29_2fa29m_hot_rolled_alloy_steel_round_bars_sae4340_10_350mm.jpg","attrs":{"Brand Name":"DELTA","Model Number":"SAE4340","Certification":"ISO","Place of Origin":"China"}}
{"title":"25Cr2MoVA Alloy Steel Round Bar Diameter 10 - 300mm Custom Cutting in Length","imgUrl":"https:\/\/img.chinax.com\/nimg\/b7\/8f\/c374af89362ac900e00ce51f86b6-200x200-1\/25cr2mova_alloy_steel_round_bar_diameter_10_300mm_custom_cutting_in_length.jpg","attrs":{"Brand Name":"DELTA","Model Number":"DIN 1.8159 (25CrMoV6-4) \/ 25Cr2MoVA","Certification":"ISO","Place of Origin":"China"}}
{"title":"EN DIN Standard 41CrAlMo7 Alloy Steel Round Bar Diameter 10 - 350mm SCM645 Alloy","imgUrl":"https:\/\/img.chinax.com\/nimg\/86\/8a\/f384d75ceea894a15b4f1ea6423b-200x200-1\/en_din_standard_41cralmo7_alloy_steel_round_bar_diameter_10_350mm_scm645_alloy.jpg","attrs":{"Brand Name":"DELTA","Model Number":"41CrAliMo7","Certification":"ISO","Place of Origin":"China"}}
{"title":"25Cr2MoVA \/ DIN1.8159 Alloy Steel Round Bar Hot Rolled Diameter 20 - 350mm in 6m","imgUrl":"https:\/\/img.chinax.com\/nimg\/55\/19\/5e678c170e39068beeabe330b547-200x200-1\/25cr2mova_2f_din1_8159_alloy_steel_round_bar_hot_rolled_diameter_20_350mm_in_6m_length.jpg","attrs":{"Brand Name":"DELTA","Model Number":"DIN 1.8159 (25CrMoV6-4) \/ 25Cr2MoVA","Certification":"ISO","Place of Origin":"China"}}
{"title":"EN 1.8507 (34CrAlMo5-10) Nitriding Steel Round Bar Diameter 10 - 300mm Custom","imgUrl":"https:\/\/img.chinax.com\/nimg\/25\/c9\/4f41b121bc96fda3bc795edf2de2-200x200-1\/en_1_8507_2834cralmo5_10_29_nitriding_steel_round_bar_diameter_10_300mm_custom_cutting.jpg","attrs":{"Brand Name":"DELTA","Model Number":"34CrAlMo5-10 \/ 1.8507","Certification":"ISO","Place of Origin":"China"}}
AISI 4340 steel is a medium carbon, low alloy steel known for its toughness and strength in relatively large sections. This nickel chromium molybdenum steel is generally supplied hardened and tempered in the tensile range of 930-1080 MPa. Pre-hardened and tempered 4340 steels can be further surface hardened by flame or induction hardening and by nitriding.
Material Specifications and Standards
Country
USA
Britain
Britain
Japan
Standard
ASTM A29
EN 10250
BS 970
JIS G4103
Grades
4340
36CrNiMo4/1.6511
EN24/817M40
SNCM 439/SNCM8
Chemical Composition
Standard
Grade
C
Mn
P
S
Si
Ni
Cr
Mo
ASTM A29
4340
0.38-0.43
0.60-0.80
0.035
0.040
0.15-0.35
1.65-2.00
0.70-0.90
0.20-0.30
EN 10250
36CrNiMo4/1.6511
0.32-0.40
0.50-0.80
0.035
0.035
≤0.40
0.90-1.20
0.90-1.2
0.15-0.30
BS 970
EN24/817M40
0.36-0.44
0.45-0.70
0.035
0.040
0.1-0.40
1.3-1.7
1.00-1.40
0.20-0.35
JIS G4103
SNCM 439/SNCM8
0.36-0.43
0.60-0.90
0.030
0.030
0.15-0.35
1.60-2.00
0.60-1.00
0.15-0.30
Mechanical Properties
Condition
Ruling Section (mm)
Tensile Strength (MPa)
Yield Strength (MPa)
Elongation (%)
Izod Impact (J)
Brinell Hardness
T
250
850-1000
635
13
40
248-302
T
150
850-1000
665
13
54
248-302
U
100
930-1080
740
12
47
269-331
V
63
1000-1150
835
12
47
293-352
W
30
1080-1230
925
11
41
311-375
X
30
1150-1300
1005
10
34
341-401
Y
30
1230-1380
1080
10
24
363-429
Z
30
1555-
1125
5
10
444-
Thermal Properties
Properties
Metric
Imperial
Thermal expansion coefficient (20°C/68°F)
12.3 µm/m°C
6.83 µin/in°F
Thermal conductivity
44.5 W/mK
309 BTU in/hr.ft².°F
Forging Process
Preheat the steel to 1150°C - 1200°C maximum for forging, holding until temperature is uniform throughout the section. Do not forge below 850°C. Following forging operations, the workpiece should be cooled as slowly as possible in sand or dry lime to prevent cracking.
Heat Treatment Procedures
Stress Relieving
Heat to 600°C - 650°C, hold until uniform temperature, soak for 1 hour per 25mm section, and cool in still air.
Annealing
Full anneal at 844°C (1550°F) followed by controlled furnace cooling at ≤10°C (50°F) per hour down to 315°C (600°F), then air cool.
Tempering
Temper at 232°C (450°F) for 260-280 ksi strength or 510°C (950°F) for 125-200 ksi strength. Avoid tempering between 250°C-450°C due to temper brittleness.
Flame or Induction Hardening
Heat to 830°C-860°C austenitic range followed by immediate oil or water quenching. Temper at 150°C-200°C to reduce case stresses.
Nitriding
Heat to 500°C-530°C for 10-60 hours to develop case depth. Achieves surface hardness of 600-650HV with minimal core strength effect.
Machining and Welding
Machining is best performed in annealed or normalized and tempered conditions. Welding in hardened and tempered condition is not recommended. If necessary, preheat to 200-300°C and stress relieve at 550-650°C after welding.
Applications
Aircraft Landing Gear
Automotive Components
Oil and Gas Drilling Equipment
Power Transmission Gears and Shafts
Heavy Duty Shafts, Axles, and Spindles
Forging Dies and Molds
General Engineering and Structural Components
Available Sizes and Conditions
Round bars: 12-380mm diameter. Available in various conditions including pre-hardened, hot rolled, annealed, quenched and tempered. Surface conditions include black, pre-machined, grinding, and polish.
Product Images
Quality Assurance and Services
Quality Commitment
ISO 9001 certified quality management system with regular audits and continuous improvement.
Timely Delivery
Speedy processing and delivery for both raw materials and finished components.
Value-Added Services
Metal cutting, sizing, machining (blanking, milling, grinding), and heat treatment services available.
Comprehensive Inventory
Unique inventory of specialty steels with orders of any size or length accommodated.
Company Details
Bronze Gleitlager
,
Bronze Sleeve Bushings
and
Graphite Plugged Bushings
from Quality China Factory
Business Type:
Manufacturer,Distributor/Wholesaler,Exporter
Total Annual:
>1000000
Employee Number:
>100
Ecer Certification：
Verified Supplier
Our company is located in Wuxi City, China, we are a stainless steel plate, seamless steel pipe, round steel, steel belt, decorative pipe and other products distribution wholesale private enterprise. Our company operates stainless steel plate, seamless steel pipe, round steel, steel belt, decorative... Our company is located in Wuxi City, China, we are a stainless steel plate, seamless steel pipe, round steel, steel belt, decorative pipe and other products distribution wholesale private enterprise. Our company operates stainless steel plate, seamless steel pipe, round steel, steel belt, decorative...
