Shearing machine blades are critical components for metal processing. High-quality industrial shear knives demand an optimal balance of high hardness, wear resistance, excellent toughness, and deep hardenability to withstand severe impact and friction during the shearing process.
Selecting the right blade material depends on three critical factors: substrate material type, sheet thickness, and production volume.
I. Common Blade Materials & Performance Profiles
1. 9CrSi (Low-Alloy Tool Steel)
Performance: Features high hardenability and tempering stability with a typical working hardness of 57–60 HRC.
Best Applications: Ideal for cutting ordinary mild steel (e.g., Q235), thin sheet metals, or non-ferrous metals (aluminum, copper).
Limitations: Highly brittle. Susceptible to chipping or premature cracking if used on stainless steel, high-strength alloys, or heavy-gauge plates. Offers a moderate service life.
2. Cr12MoV / SKD11 / D2 (High-Carbon, High-Chromium Cold Work Die Steel)
Technical Note: Cr12MoV (Chinese GB), SKD11 (Japanese JIS), and D2 (American ASTM) belong to the same metallurgical class of cold work tool steels. They share nearly identical alloy compositions and operational characteristics.
Core Performance: Reaches 58–62 HRC after quenching. Offers exceptional wear resistance, deep hardenability, and minimal dimensional distortion during heat treatment. The addition of molybdenum and vanadium significantly enhances grain structure, improving toughness and chipping resistance compared to standard carbon steels.
Best Applications: Engineered for high-volume, high-load shearing lines. Excellent for carbon steel (≤12mm), stainless steel (≤4mm), and galvanized sheets (≤20mm).
3. H13 / H13K (Premium Hot Work Die Steel)
Core Performance: Maintains a working hardness of 50–55 HRC. Engineered for maximum impact toughness and thermal fatigue resistance. It absorbs massive shock loads without structural failure or catastrophic breakage.
Best Applications: Heavy-duty guillotine shearing machines. Optimized for thick steel plates (≥20mm), hot-rolled plates, scrap metal recycling, or intermittent heavy-load shearing where impact resistance takes priority over extreme wear resistance.
4. Tungsten Carbide (e.g., WC-Co)
Core Performance: Achieves extreme hardness ratings of 89–93 HRA. Delivers wear resistance that extends service life over 10 times compared to D2/SKD11 tool steels.
Best Applications: High-speed, continuous mass production of precision thin stainless steel strips, color-coated foils, and highly abrasive, thin-gauge composite materials.
Disadvantages: Lacks impact toughness. High vulnerability to brittle fracture under shock loads. Strictly prohibited for heavy-gauge, uneven, or high-hardness thick plates.
II. Engineering Principles for Blade Selection
1. Selection by Substrate Material
Mild Carbon Steel / Aluminum Sheets: → Cr12MoV / SKD11 / D2 (Provides the best cost-to-performance ratio).
III. Technical Guidelines for Extending Blade Lifespan
Optimized Heat Treatment: Execute a strict protocol of thorough vacuum quenching combined with low-temperature tempering. This guarantees uniform volumetric hardness and eliminates localized soft spots that accelerate wear.
Precision Edge Finish: Finely grind and lap the cutting edge. A mirror-like surface finish significantly reduces friction and material pickup (galling) during operation.
Accurate Blade Clearance: Calibrate the blade gap to match the workpiece. The optimal clearance should range strictly between 5% and 10% of the material thickness. Excessive clearance creates heavy burrs and edge deformation, while insufficient clearance induces high friction, accelerating blade wear.
IV. Technical Reference Matrix
1. Comprehensive Material Properties & Application Chart
Blade Material
Material Category
Core Engineering Characteristics
Primary Target Workpieces
9CrSi
Low-Alloy Tool Steel
High hardness, economical, stable under heat treatment.
2. International Steel Grade Cross-Reference Table
China (GB)
USA (ASTM/AISI)
Japan (JIS)
Germany (DIN)
Germany (W-Nr.)
France (NF)
Russia (GOST)
U.K. (BS)
9CrSi
L3
—
90CrSi5
1.2108
—
9KhS (9ХС)
—
6CrW2Si
S1
—
60WCrV7
1.2550
55WC20
6KhV2S (6ХВ2С)
—
Cr12MoV
SKD11
X165CrMoV12
1.2601
—
Kh12M (Х12М)
—
Cr12Mo1V1
D2
X153CrMoV12
1.2379
X160CrMoV12
Kh12M1F1
BD2
4Cr5MoSiV1
H13
SKD61
X40CrMoV5-1
1.2344
X40CrMoV5
4Kh5MF1S
BH13
LD
—
—
—
—
—
—
—
W18Cr4V
T1
SKH2
S18-0-1
1.3355
HS18-0-1
R18 (Р18)
BT1
W6Mo5Cr4V2
M2
SKH9
S6-5-2
1.3343
HS6-5-2
R6M5 (Р6М5)
BM2
V. Troubleshooting & Maintenance Guide for Procurement Managers
Common Failure Modes & Field Rectifications
Micro-Chipping: Caused by improper clearance or excessive brittleness. Action: Set gap to 8%–10% of material thickness; consider switching to higher-toughness D2/SKD11 or LD steel.
Rapid Blunting: Indicates low hardness or thermal friction. Action: Ensure 60+ HRC via vacuum heat treatment and use appropriate lubricants.
Thermal Cracking (Spalling): Caused by hot-rolled plate shear fatigue. Action: Upgrade to H13 hot-work die steel for enhanced heat resistance.
Regrinding Benchmarks & Maintenance Schedules
When to Regrind: Sharpen knives immediately when the edge radius exceeds 0.3–0.5 mm. Operating with a dull edge can increase cutting forces, leading to machine frame damage.
Grinding Best Practices: Use continuous flood cooling to prevent localized overheating, which can cause cracking and permanently damage the tool.
VI. Why Sourcing Teams & OEMs Trust ALAS Industrial Tooling Solutions
NANJING ALAS INTERNATIONAL CO., LTD provides high-precision industrial blades designed to maximize uptime for global manufacturing partners.
Certified Quality Assurance: We guarantee material integrity for D2/1.2379, SKD11, and H13 steels. All shipments include EN 10204 3.1 Material Test Reports (MTRs) verified via OES spectroscopy.
Tailored Engineering & Custom OEM: Our engineers customize blade geometry, material, and heat treatment based on your specific tensile strength (UTS) and thickness requirements, ensuring the lowest total cost per cut.
VII. Custom OEM Services & RFQ Guidelines
At ALAS Machinery, we manufacture custom shear blades and replacement knives tailored to your exact machinery specifications and production challenges. Whether you need a standard replacement or a highly specialized blade for proprietary alloy cutting, we deliver precise engineering.
Compatibility with Global Machinery Brands
We engineer and supply premium-grade replacement blades fully compatible with leading shearing machine brands, including but not limited to:
Amada
Komatsu
Cincinnati
LVD
AccurPress
Pacific
Ready to Request a Quote? (RFQ Checklist)
To provide you with a fast and accurate quotation within 24 hours, please copy and email the following specifications to mt@alasmachinery.com, or attach your technical drawings:
Dimensions: Length × Width × Thickness (mm or inches)
Bolt Hole Layout: Number of holes, center-to-center hole distance, and hole type (Countersunk / Threaded / Straight)
9CrSi remains the preferred economical steel alloy for low-load, thin-gauge sheet metal shop shearing.
D2 / SKD11 / Cr12MoV represent the global industry standard for high-performance processing of abrasive materials like stainless steel and silicon sheets.
H13 is the engineering choice for high-shock, high-thickness plates, and arduous hot-rolled metal processing environments.
Nanjing Alas International Co., Ltd. is a professional industrial tooling manufacturer focused on shear blades, bending dies, shredder blades, and custom wear parts. We offer full application engineering, material selection, setup guidance, and after-sales support to global customers. Tell us your requirements, and our engineering team will provide professional solutions for blade specification, tool life optimization, and cost-effective production.
