Spherical ASTM A678 Steel Powder, grade C

ASTM A678 Steel Spherical Powder, grade C Product Information -:- For detailed product information, please contact sales. -: ASTM A678 Steel Spherical Powder, grade C Synonyms -:- For detailed product information, please contact sales. -: -:- For detailed product information, please contact sales. -: Spherical ASTM A678 Steel Powder, grade C characteristics -:- For detailed product information, please contact sales. -: Spherical ASTM A678 Steel Powder, grade C Particle Size -:- For detailed product information, please contact sales. -: -:- -:- 0-15μm ,5-25μm, 15-45μm, 15-53μm,20-63um, 45-75μm, 45-105μm, 45-150μm ,75-150μm. (Various granularities can be customized according to customer requirements) -:- For detailed product information, please contact sales. -:

Spherical ASTM A678 Steel Powder, grade C Applicable processes -:- For detailed product information, please contact sales. -: Laser/electron beam additive manufacturing (SLM/EBM, 3D printing) Direct laser deposition (DLD) Used in thermal spray (TSA) Powder hot isostatic pressing (HIP) Metal injection molding (MIM) Powder metallurgy (PM) Laser cladding (LC), etc. -:- For detailed product information, please contact sales. -: Spherical ASTM A678 Steel Powder, grade C Chemical Composition -:- For detailed product information, please contact sales. -: -:- For detailed product information, please contact sales. -: ASTM A678 Steel, grade C Product Information -:- For detailed product information, please contact sales. -: ## **Technical Specification: ASTM A678 Grade C Quenched & Tempered High-Strength Structural Steel Plate** --- ### **1. PRODUCT OVERVIEW** **Standard Designation:** ASTM A678/A678M **Full Title:** *Standard Specification for Quenched-and-Tempered Carbon and Alloy Steel Plates for Structural Applications* **Grade:** C **International Standard:** ASTM International (American Society for Testing and Materials) **Material Classification:** High-strength, quenched and tempered carbon-manganese steel plate **Strength Category:** Intermediate-high strength grade within the A678 family (65 ksi minimum yield strength) **Primary Feature:** Optimized balance of high strength, good toughness, and acceptable weldability for demanding structural applications --- ### **2. MATERIAL CHARACTERISTICS & METALLURGY** ASTM A678 Grade C is produced through a precisely controlled **quenching and tempering** heat treatment process. This involves austenitizing at appropriate temperatures, rapid quenching (typically in water or polymer solutions), and subsequent tempering to achieve the desired combination of strength and toughness. The resulting microstructure consists primarily of **tempered martensite** or **lower bainite**, providing superior mechanical properties compared to normalized or as-rolled steels of similar composition. **Key Manufacturing Advantages:** - **Through-Thickness Uniformity:** Heat treatment ensures consistent mechanical properties throughout the entire plate cross-section, minimizing property gradients. - **Enhanced Toughness:** The refined microstructure provides excellent notch toughness and impact resistance at service temperatures. - **Superior Fatigue Resistance:** The quenched and tempered structure exhibits improved fatigue strength compared to non-heat-treated steels. - **Improved Hardenability:** Controlled chemistry allows effective hardening of thicker sections while maintaining ductility. --- ### **3. CHEMICAL COMPOSITION REQUIREMENTS** The chemical composition is carefully balanced to achieve adequate hardenability during quenching while maintaining weldability and toughness after tempering. | Element | Composition (% by weight, maximum unless range is shown) | |---------|----------------------------------------------------------| | **Carbon (C)** | 0.20 - 0.28 | | **Manganese (Mn)** | 1.00 - 1.60 | | **Phosphorus (P)** | 0.035 | | **Sulfur (S)** | 0.040 | | **Silicon (Si)** | 0.15 - 0.50 | | **Copper (Cu)** | 0.20 max (report when added) | | **Nickel (Ni)** | 0.25 max (report when added) | | **Chromium (Cr)** | 0.25 max (report when added) | | **Molybdenum (Mo)** | 0.08 max (report when added) | | **Vanadium (V)** | 0.05 max (report when added) | **Carbon Equivalent (CE) Analysis:** Typical CE ranges from 0.48 to 0.58 based on IIW formula: **CE = C + Mn/6 + (Cr+Mo+V)/5 + (Ni+Cu)/15** This indicates **fair weldability** that requires careful procedure control and typically necessitates preheating for most thicknesses. **Hardenability Considerations:** The manganese and carbon ranges are optimized to ensure adequate hardenability for plates up to the maximum thickness specified while controlling the risk of quench cracking. --- ### **4. MECHANICAL PROPERTIES** #### **Minimum Required Properties (per ASTM A678):** - **Yield Strength (0.2% offset):** **65 ksi minimum (450 MPa minimum)** - **Tensile Strength:** **90 - 110 ksi (620 - 760 MPa)** - **Elongation in 8-inch gauge length:** **16% minimum** - **Elongation in 2-inch gauge length:** **18% minimum** #### **Impact Toughness (Charpy V-Notch):** - **Standard Test Temperature:** +70°F (+21°C) - **Minimum Average Energy:** **15 ft-lbf (20 J)** for three specimens - **Minimum Individual Value:** **12 ft-lbf (16 J)** for any single specimen - **Lower Temperature Testing:** Can be specified for applications requiring improved low-temperature toughness (common at 40°F/4°C or 0°F/-18°C) #### **Typical Property Range (Production Average):** - **Yield Strength:** 70 - 75 ksi (typical production range) - **Tensile Strength:** 95 - 105 ksi (typical production range) - **Yield-to-Tensile Ratio:** 0.70 - 0.75 - **Hardness:** 240 - 280 HB (Brinell) - **Modulus of Elasticity:** 29,000 ksi (200 GPa) - **Shear Modulus:** 11,500 ksi (79 GPa) - **Reduction of Area:** 40 - 50% (typical) #### **Physical Properties:** - **Density:** 0.284 lb/in³ (7,850 kg/m³) - **Poisson's Ratio:** 0.29 - **Coefficient of Thermal Expansion:** 6.5 × 10⁻⁶/°F (11.7 × 10⁻⁶/°C) from 68-212°F (20-100°C) - **Thermal Conductivity:** 25 Btu·in/(hr·ft²·°F) [40 W/(m·K)] at 212°F (100°C) - **Specific Heat:** 0.10 Btu/(lb·°F) [420 J/(kg·K)] at 68°F (20°C) --- ### **5. FABRICATION CHARACTERISTICS** #### **Formability:** - **Fair to Good** for its strength level; suitable for moderate bending operations - **Minimum recommended bend radius:** 3.5 × plate thickness for 90° cold bends - Hot forming should be performed below the lower critical temperature (approximately 1300°F/705°C) and followed by appropriate heat treatment if properties are altered - Cold forming of complex shapes may require intermediate stress relief annealing #### **Weldability:** - **Fair** weldability requiring strict procedure control - **Recommended processes:** SMAW (E8018-C3 electrodes), GMAW (ER80S-D2 wire), FCAW (E81T1-Ni1), SAW (appropriate flux-wire combinations) - **Preheating requirements (essential for most applications):** - Up to 0.75" thickness: 200-250°F (95-120°C) - 0.75-1.5" thickness: 250-300°F (120-150°C) - Over 1.5" thickness: 300-350°F (150-175°C) - **Interpass temperature control:** 400-450°F (205-230°C) maximum - Post-weld heat treatment may be required for thick sections or highly restrained joints #### **Machinability:** - **Fair** (approximately 50-55% relative to AISI 1212 steel) - Requires rigid setups, positive rake tooling, and adequate cooling/lubrication - **Recommended cutting speeds:** 90-130 SFPM for turning with carbide tools - Interrupted cuts should be avoided or carefully managed #### **Cutting Operations:** - **Flame cutting:** Excellent with proper technique; preheating may be required for thicknesses over 2 inches - **Plasma cutting:** Excellent for all thicknesses with appropriate equipment - **Laser cutting:** Suitable for plates up to 1 inch thickness - **Waterjet cutting:** Excellent, no heat-affected zone concerns - **Shearing:** Limited to thinner plates (typically < 0.5 inch) due to high strength --- ### **6. PRIMARY APPLICATIONS** Grade C is specified for structural applications requiring strength significantly above conventional structural steels with good toughness and fatigue resistance. #### **Heavy Construction & Infrastructure:** - Long-span bridge girders and truss members - High-rise building transfer girders and heavily loaded columns - Crane runway girders for heavy-duty industrial cranes - Dam gate components and hydraulic structure reinforcements - Stadium roof supporting arches and tension members #### **Transportation & Heavy Equipment:** - Railroad locomotive underframes and structural components - Heavy-haul truck frames and fifth wheel assemblies - Mining shovel dipper handles and structural supports - Port crane boom sections and supporting structures - Military vehicle structural components #### **Industrial Machinery:** - Large press frames and hydraulic press cylinders - Extruder frames and heavy machinery bases - Rolling mill housings and supporting structures - Test machine loading frames and components - Industrial robot base structures and arms #### **Material Handling Systems:** - Bulk material handling conveyor trusses and supports - Stacker/reclaimer machine structural components - Heavy-duty storage rack systems for high-density storage - Gantry crane main beams and end trucks #### **Energy & Power Generation:** - Wind turbine tower flanges and base sections - Hydroelectric turbine supports and generator bases - Power plant boiler supports and structural members - Nuclear plant internal structures (where permitted by code) #### **Marine & Offshore:** - Shipbuilding components requiring high strength-to-weight ratio - Offshore platform module support structures - Deck machinery foundations and supporting structures --- ### **7. COMPARATIVE ANALYSIS** #### **Within ASTM A678 Family:** | Property | Grade B | **Grade C** | Grade D | |----------|---------|-------------|---------| | **Min Yield (ksi)** | 60 | **65** | 75 | | **Min Tensile (ksi)** | 80-100 | **90-110** | 100-120 | | **Typical CE** | 0.45-0.55 | **0.48-0.58** | 0.50-0.65 | | **Relative Cost Factor** | 1.00 | **1.10-1.20** | 1.30-1.40 | | **Weldability** | Good-Fair | **Fair** | Fair-Poor | #### **Competitive/Alternative Materials:** - **ASTM A514 Grade F:** Quenched & tempered alloy steel, similar strength (100 ksi yield) but higher alloy content - **ASTM A709 Grade 70W:** Bridge steel with weathering resistance, similar strength but different processing - **ASTM A852:** Quenched & tempered low-alloy steel with weathering resistance - **EN 10025-6 S500Q/QL:** European Q&T steel with slightly lower minimum yield strength - **JIS G3128 SGV 480:** Japanese high yield strength steel for bridges - **ASTM A6/A6M Group 4 or 5:** High-strength structural steel shapes with similar strength --- ### **8. QUALITY ASSURANCE & TESTING** #### **Mandatory Testing Requirements:** - Heat (melt) analysis for chemical composition - Tensile testing from each heat and thickness grouping - Charpy V-notch impact testing from each heat #### **Supplementary Requirements (Optional):** - **S1. Ultrasonic Examination:** For critical applications requiring verification of internal soundness - **S2. Vacuum Degassing:** For improved internal cleanliness and reduced segregation - **S3. Fine Austenitic Grain Size:** For enhanced toughness (typically ASTM grain size 5 or finer) - **S4. Charpy Impact Test Temperature:** Custom test temperatures (e.g., 0°F, -20°F) - **S5. Maximum Tensile Strength:** Upper limit specification - **S6. Tension Test Orientation:** Transverse testing requirements - **S8. Maximum Carbon Equivalent:** For enhanced weldability control #### **Standard Testing Methods:** - **Tension Testing:** ASTM A370 (longitudinal direction unless otherwise specified) - **Impact Testing:** ASTM A673 (Frequency H - each heat tested) - **Bend Testing:** ASTM E290 (when required by purchase specification) - **Hardness Testing:** ASTM E10 (Brinell) or ASTM E18 (Rockwell) - **Ultrasonic Testing:** ASTM A578/A578M (when supplementary requirement S1 is specified) --- ### **9. DESIGN & SPECIFICATION GUIDELINES** #### **Structural Design Considerations:** - Utilize 65 ksi minimum yield strength for structural calculations - Account for potential reduction in ductility compared to lower-strength steels in seismic design - Consider lamellar tearing susceptibility in highly restrained connections (use Z-quality if necessary) - For fatigue applications, consult appropriate design codes (AASHTO, AISC, API) for fatigue detail categories #### **Connection Design:** - **Bolted Connections:** ASTM A325 or A490 bolts typically used; ensure joint design accounts for higher bearing strength - **Welded Connections:** Matching strength filler metals generally recommended; consider undermatching for improved crack resistance in some applications - **Shear Connection Design:** Higher shear strength allows for more compact connections but requires careful detailing #### **Specification Language Example:** ``` Structural Steel Plate to ASTM A678/A678M, Grade C Condition: Quenched and Tempered Thickness: X.XX inches (XX mm) Width: XX inches (XXXX mm) Length: XX feet (X.X meters) Impact Test: Charpy V-notch at +70°F (21°C) Minimum Average: 15 ft-lbf (20 J) Minimum Individual: 12 ft-lbf (16 J) Supplementary Requirements: S1 (Ultrasonic Examination), S4 (Test at 0°F/-18°C) Special Requirements: [List any additional requirements] ``` --- ### **10. GLOBAL EQUIVALENTS & CROSS-REFERENCES** #### **International Standard Equivalents:** - **ISO 4950-2:** Grade 600 (similar minimum yield strength in MPa) - **EN 10025-6:** S500Q/QL/QL1 or S550Q/QL/QL1 (European Q&T structural steels) - **JIS G3128:** SGV 480/SGV 570 (Japanese high yield strength steel for welded structures) - **GB/T 16270:** Q500q/Q550q (Chinese high strength bridge steels) - **AS/NZS 3678:** Grade 500 (Australian/New Zealand structural steel) #### **Related Industry Specifications:** - **AASHTO M270M/M270:** Grades 485W/485 or HPS 485W (bridge applications) - **AWS D1.1/D1.5:** Structural Welding Code (specific requirements for high-strength steels) - **AISC 360:** Specification for Structural Steel Buildings (design values and requirements) - **API 2H:** Grade 50 (offshore platform steel with similar strength) - **ABS Steel Grades:** AH/EH 36 with higher strength requirements --- ### **11. ENVIRONMENTAL & SUSTAINABILITY** #### **Sustainability Advantages:** - **Material Efficiency:** Higher strength enables significant weight reduction in structures - **Life Cycle Performance:** Enhanced fatigue resistance can extend service life in dynamic applications - **Transportation Efficiency:** Lighter structures reduce transportation energy consumption - **Recyclability:** Fully recyclable at end of service life without property degradation #### **Environmental Considerations:** - Requires protective coating systems for corrosion protection in most environments - Compatible with advanced coating technologies including high-performance epoxies, zinc-rich primers, and metallization - Manufacturing process energy intensity is higher than for as-rolled steels but offset by life cycle benefits #### **Life Cycle Cost Benefits:** - Reduced foundation and support structure costs due to lighter weight - Lower transportation and handling costs during construction - Extended maintenance intervals with proper corrosion protection systems - Potential for longer design life in properly maintained applications --- ### **12. ORDERING & AVAILABILITY** #### **Typical Supply Parameters:** - **Thickness Range:** Commonly 0.375 to 3.0 inches (10 to 75 mm); available up to 4+ inches (100+ mm) from some producers - **Width Capability:** Up to 150 inches (3800 mm) depending on mill facilities - **Length Availability:** Typically up to 600 inches (15,000 mm) or as required - **Surface Condition:** Usually supplied with mill scale; blast cleaning available as an option - **Delivery Condition:** As heat treated (quenched and tempered) with no additional processing unless specified #### **Lead Time Considerations:** - Standard material: 6-10 weeks typical - With supplementary requirements: Additional 2-4 weeks - Heat treatment batch sizes may affect minimum order quantities and scheduling --- ### **13. FABRICATION BEST PRACTICES** #### **Storage & Handling:** - Store plates flat on level supports to prevent distortion - Use appropriate lifting equipment to avoid bending or damaging plate edges - Protect from contamination that could affect welding or coating adhesion #### **Welding Procedure Specifications (WPS):** - Require qualification testing for each WPS - Consider using undermatching filler metals for improved crack resistance in some applications - Conduct weld procedure qualification tests that include mechanical testing of weldments #### **Post-Fabrication Considerations:** - Stress relief may be necessary for complex fabrications or highly restrained joints - Final machining after welding may be required for critical dimensional applications - Non-destructive testing (NDT) of welds is recommended for critical applications --- ### **CONCLUSION** ASTM A678 Grade C represents a **high-performance structural steel** that provides an excellent balance of strength, toughness, and fabricability for demanding applications. Its 65 ksi minimum yield strength offers significant weight-saving potential compared to conventional structural steels, while the quenched and tempered condition ensures uniform through-thickness properties. **Key Value Propositions:** 1. **Superior Strength-to-Weight Ratio:** Enables lighter, more efficient structural designs 2. **Property Consistency:** Heat treatment ensures uniform mechanical properties throughout plate thickness 3. **Enhanced Toughness:** Good impact resistance for structural applications subject to dynamic loading 4. **Code Acceptance:** Widely recognized in major structural design codes and specifications **Optimal Application Scenarios:** - Structures requiring strength above A572 Grade 50/55 but where A514 Grade 100 would be excessive - Applications where through-thickness property uniformity is critical - Dynamic loading conditions requiring good fatigue resistance - Weight-sensitive designs where material efficiency directly impacts performance - Fabrications where welding is required but can be managed with proper procedures **Important Considerations:** - Welding requires careful procedure development and control - Fabrication techniques must accommodate the material's higher strength and lower ductility - Cost-benefit analysis should consider both material costs and potential savings from weight reduction - Consultation with material suppliers and fabricators during design phase is recommended When properly specified, fabricated, and maintained, ASTM A678 Grade C provides excellent long-term performance and value for high-strength structural applications across multiple industries. --- *This technical specification is based on ASTM A678/A678M-19. For critical applications, always consult the latest edition of the specification and obtain certified mill test reports. Engineering judgment should be applied for specific application requirements, and consultation with qualified metallurgical or materials engineering professionals is recommended.* -:- For detailed product information, please contact sales. -: ASTM A678 Steel, grade C Specification Dimensions Size： Diameter 20-1000 mm Length <5950 mm Size:We can customized as required Standard： Per your request or drawing We can customized as required Properties（Theoretical） Chemical Composition -:- For detailed product information, please contact sales. -: ASTM A678 Steel, grade C Properties -:- For detailed product information, please contact sales. -:

Spherical ASTM A678 Steel Powder, grade C Particle Size Description -:- For detailed product information, please contact sales. -: Applications of Spherical ASTM A678 Steel Powder, grade C -:- For detailed product information, please contact sales. -: -:- For detailed product information, please contact sales. -: Applications of ASTM A678 Steel Spherical Powder, grade C -:- For detailed product information, please contact sales. -: Chemical Identifiers ASTM A678 Steel Spherical Powder, grade C -:- For detailed product information, please contact sales. -:

Packing of ASTM A678 Steel Spherical Powder, grade C -:- For detailed product information, please contact sales. -: Standard Packing: -:- For detailed product information, please contact sales. -: Typical bulk packaging includes palletized plastic 5 gallon/25 kg. pails, fiber and Steel Spherical Powder drums to 1 ton super sacks in full container (FCL) or truck load (T/L) quantities. Research and sample quantities and hygroscopic, oxidizing or other air sensitive materials may be packaged under argon or vacuum. Solutions are packaged in polypropylene, plastic or glass jars up to palletized 2421 gallon liquid totes Special package is available on request. E FORUs’ is carefully handled to minimize damage during storage and transportation and to preserve the quality of our products in their original condition