Assab Steel Tube,Pipes, QRO 90 SUPREME Hot Work Steel Tube,Pipe

Assab Steel Tubes QRO 90 SUPREME Hot Work Steel Tube Product Information -:- For detailed product information, please contact sales. -: Assab Steel Tubes QRO 90 SUPREME Hot Work Steel Tube Synonyms -:- For detailed product information, please contact sales. -:

Assab Steels QRO 90 SUPREME Hot Work Steel Product Information -:- For detailed product information, please contact sales. -: # **Product Datasheet: Assab Steels QRO 90 SUPREME Premium Hot Work Tool Steel** ## **Product Overview** **Assab Steels QRO 90 SUPREME** is a premium **high-conductivity, high-toughness hot work tool steel** specifically engineered for **demanding die casting applications requiring superior thermal management and fatigue resistance**. As part of the advanced QRO series, QRO 90 SUPREME features a **unique alloy design with optimized chromium and vanadium content combined with elevated molybdenum**, providing exceptional **thermal conductivity, heat checking resistance, and overall die life performance**. This material represents a significant advancement over conventional H13-type steels for aluminum and magnesium die casting applications. ## **Key Characteristics & Advantages** - **Exceptional Thermal Conductivity:** 15-20% higher than standard H13 for better heat dissipation - **Superior Thermal Fatigue Resistance:** Outstanding resistance to heat checking and thermal cracking - **Excellent Toughness:** Maintains high impact strength at elevated operating temperatures - **Optimized Temper Resistance:** Balanced alloying provides good hardness retention at temperature - **Good Machinability and Polishability:** Processes well in both annealed and hardened conditions - **Reduced Soldering Tendency:** Minimizes aluminum adhesion to die surfaces - **Excellent Dimensional Stability:** Minimal distortion during heat treatment - **Proven Extended Die Life:** Documented performance in demanding applications ## **Standard Specifications & International Designations** | **Standard** | **Designation** | **Notes** | |--------------|-----------------|-----------| | **Assab/Uddeholm** | **QRO 90 SUPREME** | Premium proprietary grade | | **AISI/ASTM** | **Proprietary (Superior to H13)** | Unique chemistry | | **DIN/EN** | **1.2344 (Enhanced/Modified)** | Modified version | | **Material Category** | **Premium High-Conductivity Hot Work Steel** | For die casting | | **Primary Application** | **Aluminum & Magnesium Die Casting** | Optimized for these alloys | ## **Chemical Composition (Typical, Weight %)** | Element | Content (%) | Primary Function | Metallurgical Benefit | |---------|-------------|------------------|----------------------| | **Carbon (C)** | 0.38-0.42 | Matrix strength & carbide balance | Optimizes toughness and hardness balance | | **Chromium (Cr)** | **2.60-3.00** | **Lower than H13 for conductivity** | **Enhances thermal conductivity** | | **Molybdenum (Mo)** | **2.30-2.60** | **Higher than H13 for hot strength** | Improves high temperature strength | | **Vanadium (V)** | **0.60-0.90** | **Optimized for fatigue resistance** | Balances wear resistance and toughness | | **Silicon (Si)** | 0.25-0.45 | Deoxidizer & matrix strengthener | Cleaner steel with good strength | | **Manganese (Mn)** | 0.60-0.90 | Hardenability & strength | Consistent hardening response | | **Nickel (Ni)** | **0.25-0.45** | **Toughness enhancement** | Improves impact resistance | | **Sulfur (S)** | ≤0.005 | Machinability control | Controlled for optimal processing | | **Iron (Fe)** | **Balance** | Matrix | Structural base | ***Special Note:** The unique chemistry of QRO 90 SUPREME—characterized by **reduced chromium** (for enhanced thermal conductivity) and **increased molybdenum and nickel** (for improved hot strength and toughness)—distinguishes it from conventional H13-type steels and provides its exceptional thermal management properties.* ## **Microstructural Characteristics** | Feature | Specification | Benefit for Die Casting | |---------|---------------|-------------------------| | **Carbide Types** | Fine, evenly distributed M₆C and MC carbides | Good wear resistance without compromising toughness | | **Carbide Distribution** | Uniform throughout matrix | Consistent thermal and mechanical properties | | **Grain Structure** | Fine, equiaxed grains | Enhanced fatigue resistance and toughness | | **Microcleanliness** | High (controlled inclusion content) | Improved fatigue life and polishability | | **Phase Stability** | Excellent at elevated temperatures | Maintains properties during extended operation | ## **Typical Heat Treatment** ### **1. Annealing** - **Temperature:** **840-870°C (1545-1595°F)** - **Cooling:** Slow furnace cool (≤30°C/hour) to 500°C, then air cool - **Annealed Hardness:** **185-210 HB** - **Purpose:** Optimal condition for machining ### **2. Stress Relieving** - **Temperature:** **600-650°C (1110-1200°F)** - **Duration:** 2 hours per 25 mm thickness minimum - **Application:** After rough machining, before hardening ### **3. Hardening** 1. **Preheating:** **Two-stage recommended** - Stage 1: **600-650°C (1110-1200°F)** - Stage 2: **850-900°C (1560-1650°F)** 2. **Austenitizing:** **1000-1030°C (1830-1885°F)** - **Optimal for die casting:** **1010-1020°C (1850-1870°F)** - **For maximum toughness:** **1000-1010°C (1830-1850°F)** - **For maximum hot strength:** **1020-1030°C (1870-1885°F)** 3. **Soaking Time:** **20-40 minutes** (section size dependent) 4. **Quenching:** **Air cooling** (forced air recommended) or **high-pressure gas quenching** ### **4. Tempering** - **Critical:** **Immediate tempering** after reaching 50-70°C (120-160°F) - **Minimum Cycles:** **Double tempering** (triple recommended for critical applications) - **Temperature Range:** **540-650°C (1005-1200°F)** - **Recommended for Die Casting:** **580-620°C (1075-1150°F)** - **Hardness Profile:** - 540°C (1005°F): 48-50 HRC - 560°C (1040°F): 46-48 HRC - 580°C (1075°F): 44-46 HRC - 600°C (1110°F): 42-44 HRC - 620°C (1150°F): 40-42 HRC - 650°C (1200°F): 36-38 HRC ### **5. Nitriding (Highly Recommended)** - **Process:** **Gas or plasma nitriding** - **Temperature:** 480-530°C (895-985°F) - **Case Depth:** 0.10-0.25 mm optimal - **Surface Hardness:** 950-1150 HV - **Benefits:** Enhanced soldering resistance, improved wear resistance, extended die life ## **Physical Properties** | Property | Value | Unit | Conditions | Significance | |----------|-------|------|------------|--------------| | **Density** | 7.80 | g/cm³ | At 20°C | Similar to conventional steels | | **Modulus of Elasticity** | 210 | GPa | At 20°C | Standard stiffness | | **Thermal Expansion Coefficient** | 12.0 | ×10⁻⁶/K | 20-100°C | Slightly higher than H13 | | **Thermal Conductivity** | **28.0-30.0** | W/(m·K) | At 20°C | **Key advantage: 15-20% > H13** | | **Specific Heat Capacity** | 460 | J/(kg·K) | At 20°C | Good heat absorption | ## **Mechanical Properties** ### **Standard Condition for Die Casting (1015°C Austenitize / 600°C×2 Temper)** | Property | Value Range | Unit | Test Conditions | Significance | |----------|-------------|------|-----------------|--------------| | **Hardness** | **42-44** | HRC | Room temperature | Optimal for thermal fatigue resistance | | **Tensile Strength** | 1350-1450 | MPa | Room temperature | Good strength level | | **Yield Strength (0.2%)** | 1200-1300 | MPa | Room temperature | Adequate for die casting loads | | **Elongation** | **15-18** | % | Room temperature | **Excellent ductility** | | **Impact Toughness (Charpy V)** | **55-70** | J | Room temperature | **Exceptional toughness** | | **Thermal Conductivity** | **28-30** | W/(m·K) | Room temperature | **Primary advantage** | ### **High Temperature Performance** | Temperature | Hardness | Thermal Conductivity | Impact Toughness | |-------------|----------|----------------------|------------------| | **200°C (390°F)** | 40-42 HRC | ~26 W/(m·K) | 45-60 J | | **400°C (750°F)** | 36-38 HRC | ~24 W/(m·K) | 40-55 J | | **600°C (1110°F)** | 28-30 HRC | ~22 W/(m·K) | 30-45 J | ### **Thermal Fatigue Performance (Comparative)** | Material | Relative Thermal Fatigue Life | Key Factor | |----------|-------------------------------|------------| | **Standard H13** | 100% (Baseline) | Reference | | **QRO 90 SUPREME** | **180-220%** | **Superior conductivity** | | **8407 Supreme** | 130-150% | Good balance | | **DIEVAR** | 140-160% | Excellent toughness | ## **Primary Applications** ### **A. Die Casting – Primary Application Domain** #### **Aluminum Die Casting:** - **Large, Thick-Wall Castings:** Engine blocks, transmission cases, structural components - **Cavities and Cores with Thermal Challenges:** Where heat management is critical - **Shot Sleeves and Plunger Tips:** High thermal shock applications - **Ejector Pins and Sleeves:** In challenging thermal environments - **Dies with Uneven Wall Thickness:** Where thermal gradients are problematic #### **Magnesium Die Casting:** - **Hot Chamber Components:** Where thermal management is crucial - **Thin-Wall Magnesium Castings:** Requiring rapid heat extraction - **High-Volume Production Dies:** Where extended life is economically critical #### **Zinc Die Casting:** - **High-Volume Zinc Dies:** For extended production runs - **Precision Zinc Components:** Requiring consistent thermal conditions ### **B. Other Hot Work Applications** - **Hot Stamping Tools:** For aluminum sheet metal - **Extrusion Dies:** For non-ferrous metals - **Forging Dies:** For aluminum and magnesium - **Plastic Molding:** Hot runner systems for engineering plastics - **Glass Molding Tools:** Where thermal management is important ## **Processing Guidelines** ### **1. Machining Operations** | Operation | Tool Recommendation | Cutting Parameters | Notes | |-----------|-------------------|-------------------|-------| | **Turning** | **Carbide or coated carbide** | Speed: 90-140 m/min
Feed: 0.15-0.35 mm/rev
Depth: 2-6 mm | **Good machinability** | | **Milling** | **Carbide end mills** | Speed: 110-160 m/min
Feed/tooth: 0.12-0.28 mm | High material removal possible | | **Drilling** | **HSS or carbide drills** | Speed: 25-35 m/min
Feed: 0.12-0.25 mm/rev | Standard practices | | **Tapping** | **HSS or spiral point taps** | Speed: 6-12 m/min | Good chip formation | ***Machinability Rating:** **80-85%** (relative to 1% carbon steel = 100%) – **Better than most hot work steels*** ### **2. Grinding Operations** - **Wheel Selection:** Aluminum oxide (A46-J to A60-J) - **Coolant:** **Essential** – ample flow recommended - **Parameters:** Standard practices apply - **Surface Finish:** Can achieve **Ra < 0.1 μm** with proper technique - **Polishing:** **Excellent results** with standard polishing compounds ### **3. Electrical Discharge Machining (EDM)** - **Suitability:** **Good** – consistent material removal - **Settings:** Standard EDM parameters - **Post-EDM:** Stress relieve at 550-600°C to minimize affected layer - **Surface Quality:** Good as-edited surface ### **4. Welding and Repair** - **Weldability:** **Good to Very Good** - **Preheating:** **300-400°C (570-750°F)** - **Interpass Temperature:** Maintain above 250°C (480°F) - **Electrodes:** **Matching composition or AWS ERxxx** recommended - **Post-Weld:** Slow cool and re-temper - **Repair Success:** High success rate for die repairs ### **5. Surface Treatments** #### **Nitriding (Strongly Recommended):** - **Methods:** Gas, plasma, or salt bath nitriding - **Temperature:** 480-530°C (895-985°F) - **Case Depth:** 0.10-0.25 mm optimal - **Surface Hardness:** 950-1150 HV - **Benefits:** Enhanced performance in die casting applications #### **Other Treatments:** - **PVD Coatings:** TiN, CrN, TiAlN for specific applications - **Oxidation:** For corrosion protection - **Chromium Plating:** Limited use in specific applications ## **Quality Assurance** ### **Material Certification** | Certificate Type | Content | Standard | |------------------|---------|----------| | **3.1 Material Certificate** | Full chemical analysis, mechanical properties | EN 10204 | | **Thermal Conductivity Report** | Measured thermal conductivity values | Special test | | **Ultrasonic Test Report** | Internal soundness verification | ASTM E588 | | **Microcleanliness Report** | Inclusion content assessment | ASTM E45 | ### **Available Forms and Sizes** | Product Form | Standard Sizes | Tolerance Class | Surface Condition | |-------------|---------------|-----------------|-------------------| | **Blocks** | Up to 800×800×400 mm | ±0.5 mm | Rough machined, stress relieved | | **Round Bars** | Ø50-500 mm | h11 | Black, ground, or peeled | | **Flat Bars** | 20-300 mm thick × 100-800 mm wide | ±0.2 mm thickness | Ground surfaces | | **Custom Forgings** | Customer specifications | As per drawing | As-forged or machined | ## **Comparative Performance Analysis** ### **vs. Standard H13** | Property | QRO 90 SUPREME | Standard H13 | Improvement | |----------|----------------|--------------|-------------| | **Thermal Conductivity** | **100%** | 80-85% | **15-20% better** | | **Thermal Fatigue Life** | **100%** | 45-55% | **80-120% better** | | **Impact Toughness** | **100%** | 70-80% | **25-40% better** | | **Heat Checking Resistance** | **Excellent** | Fair-Good | **Significantly better** | | **Die Life (Typical)** | **100%** | 40-60% | **60-150% longer** | ### **vs. Other Premium Hot Work Steels** | Steel Grade | Best Application | Thermal Conductivity | Relative Cost | |-------------|------------------|----------------------|---------------| | **QRO 90 SUPREME** | High thermal stress applications | **Best** | 100% | | **8407 Supreme** | General premium applications | Good | 90-95% | | **DIEVAR** | Maximum toughness applications | Good | 95-100% | | **H13 Conventional** | Standard applications | Standard | 60-70% | ## **Application-Specific Guidelines** ### **For Optimal Die Casting Performance:** 1. **Hardness Selection:** - **Standard Cavities/Cores:** 42-44 HRC - **High Wear Areas:** 44-46 HRC - **Shot Sleeves:** 40-42 HRC - **Ejector Pins:** 44-48 HRC 2. **Heat Treatment Best Practices:** - **Austenitize at lower range** (1010-1020°C) for optimal toughness - **Double or triple temper** at 580-620°C - **Final hardness** typically 42-44 HRC for best thermal fatigue resistance 3. **Surface Treatment:** - **Nitriding highly recommended** for all die casting applications - **Case depth:** 0.15-0.25 mm optimal - **Perform after final polishing** for best results 4. **Die Design Considerations:** - **Optimize cooling channels** to leverage high thermal conductivity - **Design for thermal management** – the material's strength - **Consider thermal expansion** in fit tolerances ### **Maintenance Best Practices:** 1. **Regular Inspection:** Monitor for heat checking every 15,000-25,000 shots 2. **Stress Relieving:** Periodic at 550-600°C to extend die life 3. **Polishing:** Use appropriate compounds for best results 4. **Welding Repair:** Follow proper procedures for successful repairs 5. **Record Keeping:** Document thermal cycles and maintenance ### **Operating Parameters:** | Parameter | Recommended Range | Notes | |-----------|------------------|-------| | **Die Preheating Temperature** | 180-250°C (355-480°F) | Critical for thermal shock prevention | | **Operating Temperature** | 200-400°C (390-750°F) | Monitor with multiple thermocouples | | **Cooling Channel Temperature** | 40-90°C (105-195°F) | Optimize based on part geometry | | **Cycle Time** | Can often be reduced | Due to better heat extraction | ## **Economic Justification** ### **Cost-Benefit Analysis:** | Factor | QRO 90 SUPREME Advantage | Economic Impact | |--------|--------------------------|-----------------| | **Extended Die Life** | 60-150% longer than H13 | Reduced tooling cost per part | | **Reduced Downtime** | Fewer die changes and repairs | Increased machine utilization | | **Improved Part Quality** | Better thermal stability | Lower scrap rates | | **Potential for Faster Cycles** | Better heat extraction | Increased production capacity | | **Reduced Maintenance** | Less frequent polishing/repair | Lower labor costs | | **Total Cost of Ownership** | **Typically favorable despite higher initial cost** | **Positive ROI common** | ### **Typical ROI Scenario:** - **Material Cost Premium:** 30-50% over standard H13 - **Die Life Improvement:** 60-150% (application dependent) - **Payback Period:** Typically 6-18 months in production - **Long-Term Savings:** Significant over die lifetime ## **Technical Support Services** ### **Available from Assab/Uddeholm:** 1. **Thermal Analysis:** For die design optimization 2. **Heat Treatment Consulting:** Customized cycles for specific applications 3. **Application Engineering:** Die design for optimal thermal management 4. **Failure Analysis:** Specialized for thermal fatigue issues 5. **Performance Validation:** Application-specific testing ### **Documentation Provided:** - **Thermal Property Data:** Detailed conductivity measurements - **Heat Treatment Guidelines:** Optimized for thermal fatigue resistance - **Application Case Studies:** Real-world performance examples - **Processing Manuals:** Comprehensive machining and finishing guides --- ## **Critical Technical Notes** ### **Unique Advantages of QRO 90 SUPREME:** 1. **Proven Thermal Conductivity:** Documented 15-20% improvement over H13 2. **Optimized Chemistry:** Specifically designed for thermal management 3. **Field Validation:** Extensive successful use in demanding applications 4. **Balanced Properties:** Excellent combination of conductivity, toughness, and strength ### **Limitations and Considerations:** 1. **Lower Maximum Hardness:** Typically used at 42-46 HRC range 2. **Not for Extreme High Temperature:** Above 600°C continuous operation 3. **Cost Premium:** Higher initial investment required 4. **Optimal Application Range:** Best for thermal fatigue applications ### **Industry Acceptance:** - **Widely adopted** for large aluminum die casting applications - **Common in automotive** for engine and transmission components - **Proven performance** in high-volume production environments - **Recognized as premium solution** for thermal management challenges --- **Disclaimer:** QRO 90 SUPREME is a premium hot work tool steel specifically engineered for thermal management applications. Its advantages are most pronounced in applications where thermal fatigue is the primary failure mechanism. Consult with Assab/Uddeholm technical specialists to determine if this material is appropriate for your specific application. Performance data based on laboratory testing and field experience; actual performance may vary with specific operating conditions. Always follow current technical documentation and safety guidelines. Proper die design, heat treatment, and maintenance are essential for achieving optimal performance. -:- For detailed product information, please contact sales. -: Assab Steels QRO 90 SUPREME Hot Work Steel Specification Dimensions Size： Diameter 20-1000 mm Length <6857 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. -: Assab Steels QRO 90 SUPREME Hot Work Steel Properties -:- For detailed product information, please contact sales. -:

Applications of Assab Steel Tubes QRO 90 SUPREME Hot Work Steel Tube -:- For detailed product information, please contact sales. -: Chemical Identifiers Assab Steel Tubes QRO 90 SUPREME Hot Work Steel Tube -:- For detailed product information, please contact sales. -:

Packing of Assab Steel Tubes QRO 90 SUPREME Hot Work Steel Tube -:- 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 Tube 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 3328 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