4140 · 4340 · 42CrMo | Cr-Mo & Ni-Cr-Mo BAR STOCK
Source alloy steel bar for your forging, machining and equipment manufacturing orders. Submit the grade, diameter or section size, length, delivery condition, quantity and destination port for a factory quotation.
Compare the 3 alloy bar grades ↓Start with the material designation on your purchase order. Each grade has different alloying elements and requirements for its delivered condition.
Cr-Mo alloy steel for shafts, gear components and industrial machinery where the heat-treatment condition is specified.
Ni-Cr-Mo alloy steel for large loaded shafts, gear blanks and other heavy-duty machined components.
Cr-Mo alloy structural steel for machined parts and power-transmission components specified to GB/T 3077.
Send your combined 4140, 4340 and 42CrMo bar list, with diameter, delivered condition, quantity and destination for each item.
Compare key chemistry ranges and standards. Confirm material acceptance against the specified standard edition and heat-treatment requirements.
| Grade | Material Reference | Carbon (C) | Chromium (Cr) | Molybdenum (Mo) | Key Alloy Feature |
|---|---|---|---|---|---|
| 4140 | ASTM A322 / SAE J404 | 0.38–0.43% | 0.80–1.10% | 0.15–0.25% | Cr-Mo |
| 4340 | ASTM A322 / SAE J404 | 0.38–0.43% | 0.70–0.90% | 0.20–0.30% | Ni 1.65–2.00% |
| 42CrMo | GB/T 3077 | 0.38–0.45% | 0.90–1.20% | 0.15–0.25% | Cr-Mo |
Representative heat-analysis ranges by grade; exact limits and permitted variations are governed by the specified standard and purchase order. Grade selection requires verification of composition, heat-treatment condition and finished mechanical properties.
Chromium and molybdenum alloying for machinery parts, shafts and heat-treated bar components.
Nickel-bearing grade often selected for demanding, larger-section loaded components where the specified hardenability matters.
GB alloy structural steel for machined components; compare requirements with the approved material specification.
Use one complete enquiry to confirm available sections, nominal diameters, cut lengths, tolerances and the requested material condition.
| Available grades for enquiry | 4140, 4340, 42CrMo |
| ASTM hot-wrought alloy bars | ASTM A322-24; general requirements ASTM A29/A29M-23 |
| ASTM quenched & tempered bars | ASTM A434/A434M-24 where specified with the required strength class |
| Chinese alloy structural steel | GB/T 3077-2015 for 42CrMo |
| Bar sections | Solid round; square, hexagonal or flat by size and production availability |
| Bar dimensions | Diameter or section dimensions, length and tolerances per RFQ |
| Delivery condition | Hot-wrought, annealed, normalized or quenched & tempered, as agreed |
| Finish | Mill finish, turned / peeled / ground surface as specified and available |
| Testing & material records | Heat analysis, dimensions, hardness and mechanical test scope per contract |
| Order details | Grade, sizes, quantity, delivery condition, required documents and destination |
Select the section and surface that work with your machining, forging or parts-production drawings.
Round bar supply for forging, shaft blanks and machining stock. Share nominal diameter, length and tolerance requirements.
Request peeled, turned or ground surfaces when your component drawings call for defined finish or tighter dimensions.
Strength, hardness and machinability depend on grade, bar diameter and delivered condition. Your purchase specification defines the acceptance targets.
Mill-condition alloy steel bar for machining, forging and further processing. Grade chemistry and surface condition follow the ordered specification.
Request an annealed delivery condition for the machining or subsequent heat-treatment process stated in your part requirements.
Specify Q&T condition, required hardness or strength, bar size and the applicable test class or material drawing.
Buy the grade and delivered condition required by your component drawings, operating load and downstream manufacturing process.
Bar stock for drive shafts and coupling components machined to your drawings.
Alloy bar blanks for machining and subsequent specified heat treatment.
Large mechanical pins, pivots, forged pieces and high-load components.
Mechanical spindles, bolts and structural machine parts that call for alloy bar properties.
Specified rod stock and machined equipment components subject to application requirements.
Bar material for further hot forming and controlled heat treatment.
Get procurement support through manufacturing-scale operations, combined steel stock, materials documentation and export coordination.
Our actual annual steel production is 8 million metric tons across product categories, supporting project schedules and recurring steel orders.
Manufacturing ↗We maintain 1 million metric tons of regular combined steel inventory. Actual alloy bar availability is confirmed against your grade and dimensions.
Steel Inventory ↗Send material grade, heat treatment, hardness, mechanical tests and certificate requirements so they can be reviewed with the quote.
Quality Control ↗Submit several grades and diameters together with delivery dates and a destination port to streamline purchasing review.
Estimate nominal round bar weight from diameter, length and number of bars before you send your buying list.
Based on nominal density of 7,850 kg/m³. Theoretical weight supports planning; final delivery weight follows the purchase contract.
Coordinate scheduled bar sourcing with BAOSTEEL METAL. Our steel operations provide manufacturing scale across the company product range while your bar order is reviewed for grade, size, delivery condition and production availability.
Send your bar dimensions and heat-treatment condition to receive an availability review. The company's regular steel inventory is distributed across product families, and exact alloy bar sizes are confirmed for each order.
Specify the certificate and test scope that your fabrication team requires. Our team will confirm the available documentation and acceptance requirements for the material supplied.
Include cut lengths and drawings with your bar request. We can confirm suitable processing options, tolerances and finished quantities according to the grade, diameter and delivered condition.
Match the packing approach to your bar length, weight and handling requirements.
Secure grouping, support and lifting arrangements reviewed against bar diameter, length and shipment weight.
Grade and batch information recorded according to the purchase documentation and agreed markings.
Port, packing instructions, shipping terms and commercial documents included in the confirmed order scope.
Review grade-specific alloy properties or compare carbon and stainless steel bar families for your broader material list.
Send the grade, condition and dimensions specified for your components to receive an order-specific supply response.
Use the 4140, 4340 and 42CrMo product pages for individual grade enquiries. Include any additional grade requirements with your purchase schedule for a supply check.
4140 is primarily a chromium-molybdenum alloy steel, while 4340 also has a specified nickel range. Your component's heat treatment, dimensions and required mechanical properties guide selection.
Both grades are chromium-molybdenum alloy steels, with different standards and chemical limits. Your design and inspection requirements determine material acceptance and any approved substitution.
Send grade, applicable standard, diameter or section size, length, quantity, required heat-treatment condition, inspection needs and destination port.
Send your required grade, dimensions, quantity and destination. Our team will review the inquiry.
