How to Choose Scrap Metal Shear Blades That Won't Crack Under Pressure
In the scrap recycling industry, your scrap metal shear blades—including Demolition shear blades and Recycling shear knives—face constant extreme impact, abrasive materials, and unpredictable workloads. Scrap shearing is different from standard sheet metal cutting. It needs tools that can take massive shock without breaking—whether you’re using heavy-duty Demolition shear blades for tough debris or precision Recycling shear knives for scrap processing. Choosing the right blades (from material to manufacturing precision) decides if your operations run smoothly—or if you deal with costly downtime from cracked, chipped blades.
The Best Steel Grades for Scrap Shearing
For scrap applications, hardness isn’t everything—toughness is key. We recommend H13K or H13 Hot-Work Tool Steel. These alloys are made to handle the violent impact of cutting rebar, structural beams, and heavy plate. They won’t chip or crack. And they’re perfect for both Demolition shear blades (for rugged, oversized scrap) and Recycling shear knives (for high-volume, varied scrap).
Why Heat Treatment Is Critical
Scrap blades—whether Demolition shear blades or Recycling shear knives—often fail because of internal stress. At our factory, we use a professional manufacturing process uses multiple tempering cycles. This makes the blade’s core just as resilient as its cutting edge. This “differential tempering” lets the blade flex a little under extreme loads, instead of snapping. It extends the life of even heavily used scrap shear blades.
Precision Fit for Hydraulic Shears
Whether you use mobile eagle shears or stationary guillotine balers, a perfect fit is a must. This is especially true for Demolition shear blades and Recycling shear knives—they take constant high-impact use. Always buy from us—at our factory that uses CNC precision machining. This ensures OEM-standard tolerances, preventing misalignment that causes premature cracking and machine wear.
Scrap Metal Shear Blades technical specifications
Alligator Shear Blade
| NO. | Product Name | Specification Dimensions (length x width x height/thickness) ） | Material | Remarks |
| 18 | Alligator Shear Blade size
Scrap metal shearing blades size | 600*80*30 | H13,H13K | Customization services are available; we can manufacture according to your drawings, with a minimum order quantity of 1 piece. |
| 19 | 600*100*30mm |
| 20 | 800*120*40 |
| 21 | 800*120*50mm |
| 22 | 1000*120*40mm |
| 23 | 1000*120*50 |
| 24 | 1200*120*40 |
| 25 | 1200*120*50 |
Common Material Overview of Scrap Metal Shear Blades
The following table summarizes the type, core characteristics and main applicable shearing materials of common blade materials:
Blade Material | Material Type | Characteristics | Main Shearing Materials |
H13 (4Cr5MoSiV1) | Hot Work Die Steel | Excellent high temperature strength and thermal fatigue resistance | Hot-sheared hot rolled plate, iron plate, medium and thick plate, scrap metal, hot-sheared strip steel, cold-sheared high strength alloy steel, stainless steel thick plate |
LD (7Cr7Mo2V2Si) | Cold Work Die Steel | High strength, good toughness, wear resistance and chipping resistance, excellent comprehensive performance | High strength steel, stainless steel, thick plate and hard-to-shear metal materials (for large hydraulic shearing machines, heavy CNC shearing machines) |
Detailed Characteristics of Various Blade Materials
H13 (4Cr5MoSiV1) Hot Work Die Steel
Characteristics: Excellent high temperature strength, impact toughness and thermal fatigue resistance, can maintain good hardness and shearing performance in high temperature environment, not easy to soften and deform;
Hardness: HRC 50-55 (after heat treatment);
Applicable to: Hot shearing strip steel, hot shearing thick plate, cold shearing high strength alloy steel and stainless steel thick plate.
H13K Modified H13 Hot Work Tool Steel
Performance: An upgraded and modified version of H13, retaining the excellent impact resistance of H13 while improving core toughness, high-temperature stability, and fatigue resistance. Hardenability is superior to conventional H13;
Suitable for ≥180T ultra-large tonnage alligator shears, primarily for shearing extra-thick steel plates (≥40mm), heavy alloy steel materials, thick-walled seamless pipes, large structural steel, and other ultra-high pressure and high-impact materials, as well as ultra-heavy continuous shearing operations in scrap metal yards;
Advantages: More resistant to strong impact and fatigue than conventional H13, with a 20%-30% longer service life than H13 under ultra-heavy working conditions, making it the preferred material for ultra-large alligator shears.
LD (7Cr7Mo2V2Si) Cold Work Die Steel
Characteristics: A high-performance cold work die steel with high strength and excellent toughness. Its contained V (vanadium) and Mo (molybdenum) significantly refine the grain, giving it extremely high bending strength and toughness, better wear resistance, and extremely strong chipping resistance;
Hardness: HRC 58-62 (after heat treatment);
Applicable to: Shearing high strength steel, thick plate, stainless steel and various hard-to-shear metal materials, commonly used for blades of large hydraulic shearing machines and heavy CNC shearing machines.
Strengthening Process
The performance of the four materials depends on precise heat treatment and surface strengthening. Differences in processing can lead to more than a 2-fold difference in blade service life for the same material.
Basic Heat Treatment Process
1. Vacuum heat treatment is used instead of ordinary air quenching to reduce surface oxidation and decarburization of the blade, ensuring overall hardness uniformity;
2. Low-temperature tempering at 180-220℃ is performed immediately after quenching to eliminate internal stress, prevent blade deformation and cracking, and stabilize the core hardness and toughness of the material.
Suggestions on blade material selection
Crocodile shear blades and scrap shear blades are typically made of H13 material. For complex scrap compositions, H13K is recommended. For even higher requirements, please contact the manufacturer to discuss upgrading the material.
Blade Metal Materials International Grade Corresponding Table
China (GB) | USA(ASTM) | Japan (JIS) | Germany (DIN) | Germany (W-Nr) | France (NF) | Russia (ROCT) | U.K (BS) |
Cr12Mo1V1 | D2 | - | X155Cr12Mo12 | 1.2379 | X160CrMoV12 | - | BD |
4Cr5MoSiVI | H13 | SKD61 | X40CrMoV5-1 | 1.2344 | X40CrMoV5 | 4X5MO1C | BH13 |
LD | - | - | - | - | - | - | - |
Mechanical blades are (special wearing parts) due to different cutting products, correct and reasonable selection of materials, heat treatment hardness, grinding accuracy, packaging requirements. Please contact us before purchase and confirm whether the blade specifications materials you need are available goods.
Our quality: All mechanical parts, tools, and molds are manufactured in-house. Upon arrival at our warehouse, products undergo rigorous inspection by a dedicated quality control department. The following is our production process:
1. Blanking-choose materials according to customer requirements.
2. Forging-Forging is mainly to increase the density of the material.
3 .Annealing-to lower the temperature for processing.
4 .Finishing ---- mainly processing materials.
5 .Inspection ---- Inspect whether the product is consistent with the drawing sample.
6.Quenching ---- Improve the hardness of molded products and materials.
7 .Annealing-In order to increase the wear resistance of the product, it must be annealed for a long time to prevent the blade from breaking
8 .Tempering-mainly the parallelism of the tempering products for processing.
9 .Rough grinding ---- rough grinding the surface of the product.
10.Precision grinding ---- Super-precision grinding and mirror grinding to improve the accuracy and parallelism of the product.
11. Inspection-Let unqualified products refuse to flow into the market.
12 .Packing ---- Pack differently according to different products.