Industrial Metal Shear Blades & Knives

The Competitive Edge of Precision-Engineered Custom Blades for Metal Shearing

Material Selection: The Foundation of Quality

Cold Cutting (High Hardness)

• Materials: D2 / SKD11 (SKD11 = Cr12MoV)

• Chemical Composition (D2): C 1.40-1.60%, Cr 11.50-13.50%, Mo 0.70-1.20%, V 0.50-1.10%, Mn ≤0.60%, Si ≤0.60%, P ≤0.030%, S ≤0.030%

• Chemical Composition (SKD11/Cr12MoV): C 1.40-1.60%, Cr 11.00-13.00%, Mo 0.40-0.60%, V 0.15-0.30%, Mn ≤0.40%, Si ≤0.40%, P ≤0.030%, S ≤0.030%

• How Components Work:

• High C + Cr: Makes blades wear-resistant and easy to harden

• Mo + V: Reduces bending and makes blades tougher, preventing chipping

• Key Traits: Very hard, resists wear and bending

• Best for: Cold cutting stainless steel, low-carbon steel, aluminum, copper plates

Hot Cutting (Heat Resistance)

• Materials: H13

• Chemical Composition (H13): C 0.32-0.45%, Cr 4.75-5.50%, Mo 1.10-1.75%, Si 0.80-1.20%, V 0.80-1.20%, Mn 0.20-0.50%, P ≤0.030%, S ≤0.030%

• How Components Work:

• Cr + Mo: Keeps blades strong and resistant to heat damage at high temps

• V: Makes metal grains finer, improving toughness

• Si: Protects blades from oxidation at high temps

• Key Traits: Maintains hardness at high temps, resists heat damage

• Best for: Hot cutting strip steel, thick plates, high-temperature work

Heavy-Duty Thick Plate Cutting (Toughness)

• Materials: 6CrW2Si

• Chemical Composition (6CrW2Si): C 0.55-0.65%, Cr 1.00-1.30%, W 2.00-2.50%, Si 0.60-0.90%, Mn ≤0.40%, P ≤0.030%, S ≤0.030%

• How Components Work:

• W: Improves heat resistance and wear resistance

• Cr: Makes blades easier to harden

• Si: Boosts toughness and prevents chipping

• Key Traits: Tough, resists chipping and impact

• Best for: Cutting thick plates with high impact

Other Common Blade Materials

• 9CrSi:

• Chemical Composition: C 0.85-0.95%, Cr 0.90-1.20%, Si 1.20-1.60%, Mn ≤0.40%, P ≤0.030%, S ≤0.030%

• How Components Work: Cr = harder/wear-resistant; Si = easier to harden/tougher; C = basic cutting hardness

• Best for: Thin cold-rolled, galvanized, aluminum, copper plates; plastic, leather

• LD (7Cr7Mo2V2Si):

• Chemical Composition: C 0.65-0.75%, Cr 6.50-7.50%, Mo 1.80-2.20%, V 1.80-2.20%, Si 0.80-1.20%, Mn ≤0.50%, P ≤0.030%, S ≤0.030%

• How Components Work: V + Mo = finer grains, stronger/tougher; Cr = hard/wear-resistant

• Best for: High-strength steel, stainless steel, thick plates, hard-to-cut metals

• Powder Metallurgy Steel (ASP23/ASP60):

• Chemical Composition (ASP23): C 1.28%, Cr 4.2%, Mo 5.0%, V 3.1%, W 6.5%, Co 8.0% (typical)

• How Components Work: High V/W/Co = ultra-hard/wear-resistant; fine powder = stable/long life

• Best for: High-precision, high-frequency heavy cutting

The Importance of Precision Grinding

• Parallelism & Flatness: These reduce stress on machine parts, preventing early wear.

• Burr-free Shearing: Sharp, precision-ground blades make clean cuts. This improves product quality and eliminates extra finishing work.

Optimal Blade Gap Settings

• Match the gap to the metal’s thickness.

• Too small: Causes too much friction, dulls blades fast, may damage the machine.

• Too large: Creates rough cuts, burrs, and blade chipping.

• Check and adjust the gap often—especially when switching materials or thicknesses.

Simple Blade Material Selection Guide

• Ordinary carbon steel (Q195, Q235): 9CrSi or Cr12MoV (good value, fits all thicknesses)

• Medium/low hardness steel, aluminum/copper plates: SKD11 or D2 (wear-resistant, long life)

• Light stainless steel, medium-strength steel: SKD11 or D2 (balances wear resistance and toughness)

• Stainless steel thick plate, high-strength steel: H13 or LD (strong, tough, resists chipping)

• Hot cutting (strip steel, thick plate): H13 (heat-resistant, no softening)

• High-precision, heavy shearing: Powder metallurgy steel (ASP23/ASP60, longest life)

Key Tips for Blade Use

• Harder is not better: Balance hardness and toughness—too hard = chipping; too soft = dulling.

• Heat treatment matters: Good materials need professional heating/cooling to work their best.

• Sticky materials (stainless steel, aluminum, copper): Choose Cr12MoV or SKD11 to prevent sticking and chipping.

• Regular maintenance: Use professional shear blade sharpening and maintenance to extend blade life.

Our Key Products & Services

Hydraulic metal shear replacement blades

Scrap metal shearing knives

Custom size metal cutting blades

Shear blade sharpening and maintenance

FAQs on metal Shear Blade Selection, Precision Control and Post-operation Maintenance

I. Material Selection and Chipping Prevention

• H13K/LD: Balances hardness and toughness best. Resists impact, chipping and high temperatures. Perfect for stainless steel—no chipping when cutting up to 12mm.

• Ordinary carbon steel thick plates: Keep hardness at HRC56-59 (enough toughness to avoid breaking).

• Hard thick plates/stainless steel: Keep hardness HRC50-55. Use tough steels like H13,H13K.

• Professional check: Measure hardness from the edge to the center. Effective hardened layer ≥8-12mm = deep quenching.

• Simple check: Grind 3-5mm off the edge. If hardness drops below HRC50 = shallow quenching.

• One regrind will wear through the thin hardened layer. The inner part is soft, causing edge rolling, fast wear, more burrs and quick blade failure.

• Choose the right material: Use H13, H13K, LD or DC53. These resist high temperatures and sticking better than Cr12MoV/D2.

• Surface treatment (stops sticking/overheating):

• Vacuum nitriding: Forms a hard surface to reduce friction and stop sticking.

• PVD/TiN coating: Titanium coating resists heat and self-lubricates, reducing friction and sticking.

• Precision edge polishing: Mirror finish reduces friction between the blade and stainless steel.

II. Geometric Accuracy and Cut Quality

• Cut edges are curved/wavy (no straightness).

• Blade edge wears unevenly and gets dull faster.

• Burrs are uneven—more work to grind later.

• Severe cases: Blade scratches the plate or “gnaws” into it.

• Micro-taper edge blades: Use their taper to fix gap errors—avoids burrs (too big gap) or chipping (too small gap).

• Special edge angle: Reduces side force, fixing errors from bad gap adjustment.

• Good for: Old machines or machines with broken automatic gap adjustment.

• Steps at the blade joint.

• Double cutting, dents and step burrs.

• Plates tear or deform at the joint.

• Low-carbon steel/thin plates: 2° angle. Cuts easier, reduces machine load, no chip buildup on the edge.

• High-tensile steel/stainless steel: 1°30′ angle. Thicker, stronger edge resists chipping—trades a little cutting force for longer blade life.

III. Post-operation Maintenance and Regrinding Cost

• New blades: Check for cracks (magnetic particle/penetrant test) before flipping first time.

• Daily use: Alternate edges diagonally—don’t use one side nonstop (reduces stress).

• If the blade chipped or had heavy impact: Check unused edges for cracks before using (prevents breaking).

• Cr12MoV: 3-5 times.

• H13K/LD/DC53 (deep quenched): 6-8 times (double the life).

• Each regrind removes 0.3-0.5mm from the edge. Reduce the blade gap by 0.03-0.05mm.

• General rule: Reduce gap by ~0.04mm per regrind. Adjust slightly based on plate thickness (avoids burrs or edge wear).