1045 steel is superior to A36 for carbide snow plow blades because its medium-carbon composition allows for precise heat treatment to a hardness of 45–55 HRC, creating an unyielding, high-strength structural carrier that prevents brittle tungsten carbide insert pop-out, cracking, and premature blade failure under heavy impact. A36 steel—a low-carbon structural steel left untreated at only 20–30 HRC—flexes, deforms, and shears under cyclic loads, leading to rapid insert loss and high operational downtime. SENTHAI utilizes in-house, ISO-certified heat-treated 1045 steel carriers to guarantee maximum insert retention, superior wear resistance, and up to 10× longer wear life in demanding winter municipal operations.(Edited on Aug 9, 2026)
What Is the Steel Carrier, and Why Is It Called the “Backbone” of the Carbide Blade?
The steel carrier (or slot matrix) is the critical structural base that holds tungsten carbide inserts in place, absorbs high-energy kinetic impacts from frozen pavement, and distributes mechanical loads evenly to the plow frame.
Just as a spine stabilizes the human body, the steel carrier provides rigid structural support to hard but brittle carbide inserts. While tungsten carbide excels in abrasion resistance, its low fracture toughness makes it vulnerable to shock. If the steel carrier flexes, twists, or deforms, the stress transfers directly into the rigid brazed joint, causing the joint to shear and the carbide to crack or pop out. Without an adequately hardened carrier, even the highest premium-grade carbide is wasted.
1045 Steel vs A36: Chemical Composition and Metallurgy
The performance gap between 1045 and A36 steel stems directly from their chemical compositions and heat treatment capabilities.
Carbon Content Difference: 1045 is a medium-carbon steel containing 0.43%–0.50% carbon. This elevated carbon level gives 1045 high hardness potential and an excellent response to heat treatment (quenching and tempering). A36 is a low-carbon structural steel with only 0.25% maximum carbon, making it impossible to harden above 30 HRC through standard thermal processing.
Manganese and Alloy Balance: 1045 steel contains 0.60%–0.90% manganese, enhancing hardenability, tensile strength, and internal toughness across thick structural plate sections.
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| Property / Parameter | 1045 Steel (Heat-Treated) | A36 Steel (Untreated) |
+--------------------------+----------------------------+----------------------------+
| Carbon Content (%) | 0.43% – 0.50% (Medium) | 0.25% Max (Low) |
| Hardness (Rockwell C) | 45 – 55 HRC | 20 – 30 HRC (70–80 HRB) |
| Tensile Strength (MPa) | 650 – 850 MPa | 400 – 550 MPa |
| Yield Strength (MPa) | 450 – 600 MPa | 250 – 350 MPa |
| Impact / Flex Resistance | High (Resists deformation) | Low (Bends under load) |
| Carbide Retention | Rigid pocket (No pop-out) | Soft pocket (Micro-moves) |
| Machinability Index | Excellent for precision | Sticky / General fab |
| Weldability | Requires preheat/control | Excellent / Easy to weld |
| Expected Wear Lifespan | 5× – 10× Longer | Short (Frequent swaps) |
| Ideal Application | Heavy-duty/Municipal/Fleet | Light-duty / Occasional |
+--------------------------+----------------------------+----------------------------+
Mechanical Performance: Hardness, Yield Strength, and Wear Resistance
Hardness & Pocket Rigidity
Hardness measured on the Rockwell C scale (HRC) directly dictates pocket integrity. The optimal carrier hardness range for snow plow blades is 45–55 HRC. At this level, the steel resists localized crushing around the insert slot. A36 steel remains at 20–30 HRC; under heavy impact against manhole covers or uneven pavement, its soft pocket walls yield, causing micro-movements that shear the brazed bond.
Yield Strength & Flex Deflection
Heat-treated 1045 delivers a yield strength of 450–600 MPa, compared to just 250–350 MPa for untreated A36. Under high-speed plowing, A36 undergoes plastic deformation and flex deflection. When the base bends, the non-flexible carbide tip fractures instantly.
Wear Resistance & Abrasive Life
The higher carbon matrix and martensitic microstructure of tempered 1045 steel provide exceptional resistance to sand, gravel, and salt slurry abrasion, preventing premature steel washing around the carbide cutting edge.
Machinability, Weldability, and Fabrication Differences
Machinability for Precision Slotting
Machining high-precision insert slots requires clean dimensional tolerances. 1045 steel in its normalized state machines cleanly, allowing precise milling of insert pockets for tight mechanical fitment before heat treatment. A36 tends to be gummy during high-speed milling, leading to slot variations that weaken insert adhesion.
Weldability and Thermal Care
A36 Steel: Extremely easy to weld without strict thermal management due to low carbon content. It is widely used in general structural fabrication, frames, brackets, and supports.
1045 Steel: Higher carbon content increases hardenability and crack sensitivity in the Heat-Affected Zone (HAZ). Welding 1045 steel—or joining 1045 to A36 structural components—requires precise preheating (200°C–300°C), controlled interpass temperatures, and slow cooling to ensure joint integrity without embrittlement.
How Heat Treatment Transforms 1045 Steel into an Elite Carrier
Raw 1045 steel requires a controlled four-stage thermal process to achieve structural toughness without brittleness:
Normalizing: Heating the steel to refine internal grain structure and eliminate rolling stresses.
Austenitizing: Heating to 840°C–870°C to transform the phase structure into uniform austenite.
Controlled Oil Quenching: Rapid cooling in oil to form a hard, fully martensitic grain structure.
Precision Tempering: Reheating to 400°C–500°C to stress-relieve the steel, balancing high hardness (45–55 HRC) with high impact toughness.
SENTHAI manages full-process heat treatment in-house at its automated facility in Rayong, Thailand. Every production batch undergoes multi-point Rockwell C testing under ISO 9001 and ISO 14001 quality standards, eliminating structural weak spots across the entire blade length.
What Happens When the Carrier Is Too Soft? (3 Failure Modes)
Insert Pop-Out: Under heavy road impacts, a soft A36 carrier deforms, widening the slot pocket until the carbide falls out entirely.
Blade Bending and Uneven Wear: Lower yield strength allows the carrier to bow, causing uneven pavement contact, blade chatter, and rapid single-sided wear.
Fatigue Cracking and Structural Breakage: Repeated stress cycles form micro-cracks in soft, un-tempered steel, leading to catastrophic blade failure mid-route.
SENTHAI Engineering & Industry Perspective
“Over 21 years of manufacturing carbide wear components, we have seen that the steel carrier is the foundation of total blade lifespan. Many fleet operators focus solely on tungsten carbide grades, but if the carrier base is soft, even top-tier carbide cannot stay seated. That is why we mandate in-house heat-treated 1045 steel for all our JOMA Style Blades, I.C.E. Blades, and Carbide Snow Plow Blades. Operating fully automated lines in Rayong, Thailand, we control everything from powder metallurgy and wet grinding to induction brazing, vulcanization, and heat treatment. Municipal fleets switching from untreated A36 to SENTHAI heat-treated 1045 carriers routinely double or triple their operational blade life while drastically reducing seasonal change-out costs.”
Cost-Benefit Analysis: Upfront Price vs. Cost Per Operating Hour
While raw A36 steel is cheaper upfront, it creates high long-term operational expenses due to frequent replacements and labor downtime.
A36 Blades: Low initial purchase price, but heavy-duty users often replace blades 2 to 3 times per season due to insert loss, bending, or excessive wear.
Heat-Treated 1045 Blades: Higher upfront investment, but lasts 5× to 10× longer. One municipal fleet utilizing SENTHAI heat-treated 1045 blades recorded a 60% reduction in seasonal blade change-outs, fully recovering the price difference within the first major winter storm.
Frequently Asked Questions
Q1: Can A36 steel ever be heat-treated to match 1045 hardness?
No. A36 contains a maximum of 0.25% carbon, which is chemically insufficient to form a high-hardness martensitic structure. Quenching A36 will not yield hardness above 30 HRC. Only medium-carbon steels like 1045 (0.45% C) or alloy steels like 4140 achieve 45–55 HRC.
Q2: Is 1045 steel stronger than A36 steel?
Yes. Heat-treated 1045 steel exhibits significantly higher tensile strength (650–850 MPa vs. 400–550 MPa) and higher yield strength (450–600 MPa vs. 250–350 MPa) than A36.
Q3: Does high hardness make a 1045 steel carrier brittle?
Not when properly quenched and tempered. Precise tempering restores ductility and impact resistance, allowing 1045 steel at 45–55 HRC to absorb high kinetic shocks without cracking.
Q4: Is A36 better than 1045 for any applications?
Yes. A36 is preferred for general structural fabrication, building frames, mounting brackets, and simple welded assemblies where low cost, easy cold-forming, and effortless welding are prioritized over wear resistance or high strength.
Q5: Can 1045 and A36 be welded together on a plow assembly?
Yes, but the process must accommodate the higher hardenability of 1045. Pre-heating the 1045 side to 200°C–300°C and using low-hydrogen filler metals prevents cracking in the heat-affected zone.
Q6: How can I verify if my plow blade has a heat-treated 1045 carrier?
Request a Material Test Report (MTR) or a certified hardness test certificate from your manufacturer showing 45–55 HRC readings. You can also perform a physical bench hardness test or file test.
Final Recommendation
When choosing between 1045 steel and A36, match the material to the mechanical requirement: choose A36 for low-cost, general structural welding, and choose heat-treated 1045 steel for strength-critical, high-wear components like carbide snow plow carriers.
Investing in a properly hardened 1045 carrier eliminates premature insert pop-out, protects your tungsten carbide investment, and minimizes seasonal downtime. SENTHAI provides fully customized blade lengths, mounting hole patterns, and carbide insert configurations manufactured under strict ISO 9001 quality controls. Visit senthaitool.com to review detailed material specifications or request a custom quote for your fleet.