Belzona 4301
Magma CR1 Hi-Build
A high-performance, paste-grade epoxy with outstanding resistance to concentrated inorganic acids and alkalis.
A high-performance, two-component, paste-grade epoxy with outstanding resistance to concentrated inorganic acids and alkalis. Used for rebuilding chemically wasted surfaces and as a repair filler beneath Belzona chemical-resistant coatings.
- SeriesBelzona 4000 Series
- Documents4
Overview of Belzona 4301
Belzona 4301 (Magma CR1 Hi-Build) is a high-performance, two-component paste-grade epoxy with outstanding chemical resistance, especially to concentrated inorganic acids and alkalis. Engineered for rebuilding and repairing surfaces that have been wasted through chemical attack, the system delivers Shore D 80 hardness, 13,089 psi proportional limit compressive strength at ambient cure, and resistance to 98% sulfuric acid (less than 0.2% weight loss after 7 days at 20°C).
Used as a repair filler ahead of Belzona 4311, 4331, or 4341 chemical-resistant coatings, or as a standalone profiling and fairing compound for rough surfaces. Force-curing at 80°C (176°F) for 4 hours optimizes chemical resistance for the most aggressive service. Slump resistance of zero at 12.7 mm (0.5 inch) enables vertical and overhead application without specialized tooling.
Key Benefits
Outstanding resistance to a wide range of chemicals
Exceptional compressive strength for load-bearing applications and demanding mechanical environments
100% solids formulation reduces health and safety risks in confined spaces with no shrinkage on cure
No solvents, no shrinkage during cure
Bonds strongly to virtually any rigid surface
Easy to mix and apply without specialist tools
Application Areas
What this product handles, grouped by equipment area — each links to the full application.
Tanks & Chemical Containment Areas
6 applications- Chemical containment liningProtection of tanks and secondary containment areas from chemicals and the effects of corrosionLearn more
- Acid-retaining walls, drains & channelsAcid retaining walls subject to thermal cycling or substrate movementLearn more
- Pump bases & tank padsPump bases, pump casings, and tank padsLearn more
- Flange face & nozzle insert repairDamaged or worn flange faces and nozzle insertsLearn more
- Pit filling & chemically-wasted surface rebuildPit filling and rebuilding of chemically wasted surfacesLearn more
- Surface profiling & fairingProfiling and fairing rough surfaces ahead of Belzona chemical-resistant coatingsLearn more
Technical Data
Composition
- Type
- Two-component, paste-grade epoxy chemical resistant filler
- Mixing Ratio by Weight (Base : Solidifier)
- 2 : 1
- Mixing Ratio by Volume (Base : Solidifier)
- 2 : 1
Components
- Base
- Paste, red, gel strength 230 g/cm (HF paddle), density 1.50 g/cm³
- Solidifier
- Paste, black, gel strength 170 g/cm (QH paddle), density 1.50 g/cm³
Mixed Properties
- Color
- Red
- Density
- 1.50 g/cm³
- Form
- Paste
- Slump Resistance
- Nil at 12.7 mm (0.5 inch)
- VOC (ASTM D2369 / EPA ref. 24)
- 0.12% (1.85 g/L)
- Resistance to 98% Sulfuric Acid
- Less than 0.2% weight loss of cured coupon after 7 days immersion at 20°C (68°F)
Application
- Application Methods
- Plastic applicator, spatula, or short-bristled brush
- Application Temperature Range
- 10°C (50°F) to 40°C (104°F)
- Volume Capacity
- 667 cm³ (40.7 in³) per 1 kg unit
- Force Cure (optimum)
- 80°C (176°F) for 4 hours — ensures very best chemical resistance
Compressive Properties (ASTM D695)
68°F/20°C cure & test
- Compressive Strength
- 13,089 psi (90.2 MPa)
- Proportional Limit
- 10,692 psi (73.7 MPa)
- Young's Modulus
- 2.10 × 10⁵ psi (1,450.9 MPa)
212°F/100°C cure & 68°F/20°C test
- Compressive Strength
- 16,770 psi (115.6 MPa)
- Proportional Limit
- 12,516 psi (86.3 MPa)
- Young's Modulus
- 2.54 × 10⁵ psi (1,752.5 MPa)
Flexural Properties (ASTM D790, 20°C/68°F)
- Flexural Strength (Maximum)
- 66.8 MPa (9,690 psi)
- Flexural Strength (Yield)
- 47.2 MPa (6,850 psi)
- Flexural Modulus
- 4,448 MPa (6.45 × 10⁵ psi)
Tensile Properties (ASTM D638)
- Tensile Strength (68°F/20°C cure)
- 6,759 psi (46.60 MPa)
- Tensile Strength (212°F/100°C post-cure)
- 8,305 psi (57.26 MPa)
- Elongation (68°F/20°C cure)
- 0.92%
- Elongation (212°F/100°C post-cure)
- 1.19%
- Young's Modulus (68°F/20°C cure)
- 9.43 × 10⁵ psi (6,499 MPa)
- Young's Modulus (212°F/100°C post-cure)
- 9.35 × 10⁵ psi (6,450 MPa)
Adhesion
- Tensile Shear, grit blasted steel (ASTM D1002)
- 19.4 MPa (2,820 psi)
- Pull-off, mild steel (ASTM D4541/ISO 4624)
- 35.1 MPa (5,090 psi)
- Pull-off, dry concrete with Belzona 4911 conditioner
- 8.1 MPa (1,170 psi)*
- Pull-off, damp concrete with Belzona 4911 conditioner
- 7.4 MPa (1,080 psi)*
- * Cohesive failure of concrete — bond exceeds substrate strength
Hardness
- Shore D (ASTM D2240)
- 80
- Barcol (Model 935, ASTM D2583)
- 85
Abrasion (Taber, ASTM D4060, 1 kg load, per 1,000 cycles, 20°C/68°F cure)
- Dry (CS17 wheels)
- 44 mm³
- Wet (H10 wheels)
- 833 mm³
Impact Resistance (Izod Pendulum, ASTM D256)
68°F/20°C cure & test
- Reversed Notched
- 2.7 KJ/m² (28.8 J/m)
- Un-Notched
- 5.9 KJ/m² (62.7 J/m)
212°F/100°C post-cure
- Reversed Notched
- 3.5 KJ/m² (44.6 J/m)
- Un-Notched
- 7.5 KJ/m² (93.8 J/m)
Heat Resistance
- HDT (ambient cure, ASTM D648, 1.8 MPa fiber stress)
- 48°C (118°F)
- HDT (100°C post-cure)
- 78°C (172°F)
- Glass Transition Temperature Tg (ambient cure, ISO 11357)
- 57°C (134°F)
- Glass Transition Temperature Tg (100°C post-cure)
- 94°C (201°F)
- DSC degradation onset (ISO 11357)
- 210°C (410°F)
- Service
- lower limit -40°C (-40°F), upper dry 80°C (176°F), upper wet 60°C (140°F)
Chemical Resistance
- Excellent resistance to a broad range of chemicals, particularly strong and concentrated inorganic acids and alkalis
- Refer to Chemical Resistance chart for detailed compatibility information
Shelf Life
- Separate Base and Solidifier components have a 3-year shelf life from date of manufacture in original unopened containers stored between 5°C (41°F) and 30°C (86°F)
Working Life
From commencement of mixing, use within:
- 50°F (10°C)
- 80 minutes
- 68°F (20°C)
- 40 minutes
- 86°F (30°C)
- 30 minutes
- 104°F (40°C)
- 20 minutes
Curing Time
Allow Belzona 4301 to solidify before subjecting it to the conditions indicated:
At 50°F (10°C)
- Dimensionally stable
- 18 hours
- Machining
- 24 hours
- Full chemical resistance
- 14 days
At 68°F (20°C)
- Dimensionally stable
- 6 hours
- Machining
- 12 hours
- Full chemical resistance
- 7 days
At 86°F (30°C)
- Dimensionally stable
- 5 hours
- Machining
- 10 hours
- Full chemical resistance
- 6 days
At 104°F (40°C)
For optimum chemical resistance: allow to reach dimensional stability, then force cure at 176°F (80°C) for 4 hours.
- Dimensionally stable
- 3 hours
- Machining
- 6 hours
- Full chemical resistance
- 5 days
Service Temperature Limits
- Service Temperature (lower limit)
- -40°C (-40°F)
- Service Temperature (dry, upper limit)
- 80°C (176°F)
- Service Temperature (wet, upper limit)
- 60°C (140°F)
- Heat Distortion Temperature (ambient cure)
- 48°C (118°F)
- Heat Distortion Temperature (100°C post-cure)
- 78°C (172°F)
- DSC degradation onset
- 210°C (410°F)
- Application Temperature Range
- 10°C (50°F) to 40°C (104°F) ideally; below 10°C cure times extend significantly and chemical resistance is reduced
- Storage Temperature
- 5°C (41°F) to 30°C (86°F) in unopened containers
Product PDFs
Gallery
Frequently Asked Questions
What is a chemical-resistant coating?
Belzona engineers chemical-resistant coatings, which are epoxy-based liquid or paste-grade coatings that provide a barrier between harsh acids and alkalis and the substrate. The coating protects the substrate from chemical attack and endures the chemical attack instead. Belzona 4301 (Magma CR1 Hi-Build) is a high-build version of the Magma CR1 system designed to achieve thicker films in fewer coats for chemical containment and pump volute protection.
What is the mixing ratio of Belzona 4301 (Magma CR1 Hi-Build)?
The mixing ratio of the high-build chemical-resistant coating, Belzona 4301 (Magma CR1 Hi-Build), is 2 : 1 (Base : Solidifier) by weight and 2 : 1 (Base : Solidifier) by volume. Please see the Product Specification Sheet (PSS) for more information.
How do you apply Belzona 4301 (Magma CR1 Hi-Build)?
To apply the chemical-resistant coating, Belzona 4301 (Magma CR1 Hi-Build), the surface must be clean, firm, and dry, free of rust, paint, and other surface coatings and contaminants. Condition the area using Belzona 4911 (Magma TX Conditioner). Add the entire contents of the Solidifier component to the Base unit and mix thoroughly until a completely homogeneous paste is achieved. Apply the material using a short-bristled brush or trowel to the prepared surface. A second coat can be applied as soon as the first coat is firm enough. Please see the Instructions for Use (IFU) for more information.
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